The Well Plated Cookbook is now available for pre-order! Blueberry Oatmeal Bars
These Blueberry Oatmeal Bars are wise teachers in the beauty of simplicity in cooking and baking. I am often tempted by the idea that the more ingredients I add to a recipe, the better the dish will taste. These easy blueberry oatmeal bars prove me wrong with every bite. They couldn’t be easier to make, I’d wager you have all the ingredients you need to make them in your pantry right now, and the only thing I could possibly add to make them taste even better is a scoop of vanilla ice cream!
This idea that simple is often better in cooking is a lesson I know I’m going to keep learning over and over. I might even have to eat a few extra blueberry oat bars to continually refresh my memory. It’s a hard order, but life lessons are life lessons, and it’s important that I stay sharp.
I adapted these Blueberry Oatmeal Bars from one of the all-time most popular recipes on my site, these healthy Strawberry Oatmeal Bars. Both are fresh, fruity, and showered in buttery crumble topping. Both need only one bowl to prepare. Both even clock in at approximately 100 calories. Swap that ice cream I mentioned earlier for a scoop of Greek yogurt, and you can be eating baked strawberry or baked blueberry bars at breakfast.
Although I’m not going to be committing myself to a single fruit bar recipe for the rest of my life anytime soon (particularly with such delights as Caramel Apple Bars and Cherry Bars to consider), these Blueberry Oatmeal Bars do have a serious advantage over any other oatmeal crumble bar I’ve ever baked: blueberries take exactly zero prep work.
Blueberries don’t need to be sliced like strawberries, pitted like cherries, or peeled like apples. In fact, you don’t need to do another blessed thing, other than prevent yourself from eating them all before you’ve finished the recipe.
It feels especially appropriate to be sharing this Blueberry Oatmeal Bar recipe today, because I’m currently in a place that does simplicity perhaps better than any other: Italy. In case you missed Tuesday’s update, I’m spending five days in Verona learning all about how fresh pasta is made, then heading to Paris for a few days to revisit all of my favorite Parisian bakeries and chocolate shops. ? Be sure to follow my Instagram (I’ll be sharing both posts and stories), and I’ll eventually be sharing a recap of my trip here too.
Wishing you all a sweet weekend, with a pan of Blueberry Oatmeal Bars to go along with it!
Recipe Adaptations
- To Make Gluten Free. Be sure to use certified gluten-free oats like these and swap the white whole wheat flour for a 1:1 baking blend (I’ve had good luck with this one).
- To Use Frozen Blueberries. I have not tried this recipe with frozen, thawed blueberries, but I think that it would work. Be sure to thaw the blueberries completely first.
- To Double the Recipe. The recipe can be doubled and baked in a 9×13-inch baking pan. The bars will be a bit thicker but still delicious.
More Blueberry Recipes
Recommended Tools to Make This Recipe
- Favorite 8×8 inch baking pan
- Parchment paper (I love these pre-cut sheets)
Blueberry Oatmeal Bars
Ingredients
FOR THE BLUEBERRY OATMEAL BARS:
- 1 cup old-fashioned rolled oats - gluten free if needed
- 3/4 cup white whole wheat flour - or substitute all-purpose flour or, to make gluten free, 1:1 baking flour
- 1/3 cup light brown sugar
- 1/2 teaspoon ground cinnamon
- 1/4 teaspoon kosher salt
- 6 tablespoons unsalted butter - melted (or substitute melted coconut oil to make vegan/dairy free)
- 2 cups fresh blueberries* - about 10 ounces
- 1 teaspoon cornstarch
- 1 tablespoon freshly squeezed lemon juice - from about 1/2 small lemon
- 1 tablespoon granulated sugar - divided
FOR THE VANILLA GLAZE (OPTIONAL BUT DELICIOUS, ESPECIALLY IF YOU PREFER A SWEETER BAR):
- 1/2 cup powdered sugar - sifted
- 1/2 teaspoon pure vanilla extract
- 1 tablespoon milk - any kind you like
Instructions
- Place a rack in the center of your oven and heat to 375 degrees F. Line an 8x8-inch baking pan with parchment paper so that the paper overhangs two sides like handles.
- In a medium bowl, combine the oats, white whole wheat flour, brown sugar, cinnamon, and salt. Pour in the melted butter and stir until it forms clumps and the dry ingredients are evenly moistened. Set aside 1/2 cup of the crumble mixture, then press the rest into an even layer in the bottom of the prepared pan.
- Scatter half of the blueberries over the crust. Sprinkle the cornstarch evenly over the top, then sprinkle on the lemon juice and 1/2 tablespoon granulated sugar. Scatter on the remaining berries, then the remaining 1/2 tablespoon sugar. Sprinkle the reserved crumbs evenly over the top. You will have some fruit showing through.
- Bake the bars for 30 to 40 minutes, until the fruit is bubbly and the crumb topping smells toasty and looks golden. Place the pan on a wire rack to cool completely (you can speed this process along in the refrigerator).
- While the bars cool, prepare the glaze: in a medium bowl, briskly whisk together the powdered sugar, vanilla, and milk until smooth. Feel free to add more milk if a thinner consistency is desired. Using the parchment paper handles, lift the bars from the pan. Drizzle with the glaze, slice, and serve.
Notes
- *I have not tried this recipe with frozen, thawed blueberries, but I think that it would work. Be sure to thaw the blueberries completely first.
- The recipe can be doubled and baked in a 9x13-inch baking pan. The bars will be a bit thicker but still delicious.
- To make the bars gluten free, substitute the white whole wheat flour with a 1:1 baking mix like this one.
- Store leftovers in the refrigerator for up to 5 days.
- To freeze, let the bars cool completely and do not glaze. Wrap tightly in plastic before placing in the freezer. Let thaw in the refrigerator and top with glaze before serving. (Bars can be frozen already glazed if needed.)
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These blueberry oatmeal bars look AMAZING! :D I hope you have an amazing rest of your trip in Italy and Paris!! <3
Thanks so much, Sarah!
These look delicious, and would be a great addition to my breakfast bakes rota. Thanks for sharing, Erin!
Lo
http://www.themixtures.com
Thanks, Lo! I hope you love them if you do give the recipe a try!
Could you make these with honey or maple syrup instead of brown sugar?
Hi Megan! I’ve never tried that, and to be honest, I probably wouldn’t recommend it, because honey and maple syrup are both very liquidy and I don’t think that the crumb or crust would set properly. If you want to try a different sweenter, you could experiment with coconut sugar. I’d add one more tablespoon of butter, since coconut sugar can be kind of dry, so you’ll want more moisture. I hope that helps, and if you do try coconut sugar, I’d love to hear how it turns out!
I can’t wait to make this. It sounds so good! Thank you!!! ☺ you always surprise us with fun recipes to make.
Hazel, thank YOU for the kind words—they mean a lot, and I hope you love the bars!
This is the kind of thing I need for energy in the morning! (;
hey girl- these look so yummy! Have a great weekend!
Thank you Shawnna! You have a great weekend too :-)
HI Erin! We live and blog in Paris! Hope you’re having an amazing time and enjoying this gorgeous Spring weather we’re having!
Thank you, Alix!!
Baked goods with blueberries in them are awesome. These look so good, and the photography is amazing too! Thanks for the recipe Erin!
Hi Erin, I’m looking forward to trying this recipe with blueberries, and your healthy strawberry oatmeal bars. Since I didn’t have strawberries or blueberries on-hand, I did make this recipe as written, except used a cup of diced apple (with a touch of cinnamon) and a cup of thawed cranberries in place of the blueberries/strawberries. It was delicious. This is such an easy, versatile, and tasty recipe; one we plan to enjoy often. Thank you for sharing your recipes (love the flourless peanut butter oatmeal bars with chocolate chips too!).
PS I also enjoyed the post you shared with the healthy strawberry oatmeal bars recipe.
Becky, I’m so glad you enjoyed the bars! The apple/cranberry version sounds delicious. Thank you for taking the time to leave this nice comment and share your tweaks!
This looks so delicious! Wish I could reach through my screen and eat it now!
I’m new to the realm of baking, and you could even say cooking for that matter! I was a little worried about how this recipe would turn out, but I have to say it was amazing!! Fresh blueberries were a little expensive last week, so I thawed out some frozen ones, and it turned out great :) I also used coconut oil instead of butter like you suggested in the recipe, and it added the perfect subtle hint of coconut to the recipe that felt like it was always supposed to be there. AMAZING. WILL DEFINITELY MAKE AGAIN. I have to say I’m enjoying making many of your recipes throughout the last few months!
Sarah, you are so sweet! Thank you so much for your kind words about my recipes, and I’m so excited to hear that you loved this one! I really appreciate your taking the time to report back and leave this review. :)
Hi! In the recipe you say any milk can be used. Would almond milk work?
Hi Sylvia, yes, almond milk will work!
I made this with “brown” whole wheat flour and frozen berries since that’s all I had in the house, and it turned delicious. But I overlooked them a little since I used a 9×13 and it was hard to tell when they were done with the brown whole wheat. Next time I will definitely use an 8×8. I’m a huge fan of all your recipes, as much as your sense of style and humor. Thanks for the cooking inspiration!
I’m so happy you loved the bars Anne! I think once you use the 8×8 like in the recipe, it will go really smoothly. Thanks for trying the recipe and taking time to report back!
These were delicious! I used frozen blueberries, which I defrosted on paper towel to absorb the excess moisture. The only problem I had was with printing the recipe. The document was six pages long. The recipe itself was only on one of these pages, but the font was so small that I could barely read it. I had to transfer the information to a Word document and fix it. No matter, the recipe is worth it!
Hi Jocelyn! I am so happy to hear that you loved the recipe! I’m sorry about the printing issue—I haven’t heard that before, but I am going to look into it right away.
Would this work without corn starch? What does it do? Thanks!
Hi Emily! I have not tried these bars without the cornstarch, and I’m afraid they may not set up as well. You could try swapping in arrowroot powder, but it would be an experiment. If you decide to play around with it, I’d love to hear how it goes!
hey girl- these bars look so yummy!
Amazing. These are easy to make and difficult to stop eating!
Thanks so much for taking the time to leave this review, Donna! I’m so glad to hear you enjoyed the bars.
This recipe was super easy & unbelievably delicous!. I left off the glaze and used blueberrys i had frozen earlier in the season. This is my new go to blueberry dessert
YAY I’m so excited to hear this was a winner! Thanks so much for taking the time to leave this awesome review. :)
WOW! is all I can say.. So easy and delicious..
Thank you so much, Liz!
These are delicious! I am a tough judge, but I have made these twice already! This recipe is the perfect use for the blueberries that we have been getting in our CSA box. Not to mention, a great balance of healthy and yummy! I like bigger sized bars so they are a little higher calories, but not crazy! I use coconut oil, which pairs nicely with the blueberries. The most recent batch I made, I threw some in the freezer for a late night treat.
I can say enough about these! Try them for yourself! Thank you SOOOOO much for sharing! They are in the regular routine!
YAY Abbi! I’m so glad to hear these bars are a winner for you! Thanks so much for taking the time to share this awesome review. :)
I was looking for a dessert to bring to my mom’s for a family dinner last week, and these were perfectly received by everyone! I served them with a scoop of vanilla ice cream as suggested, and you’re right Erin, it took them over the top! I also love that they don’t have a ton of added sugar. Thanks for such a fab recipe.
YAY Sarah, I’m so happy to hear this recipe was a winner with your family! Thank you so much for giving it a try and taking the time to report back. :)
I’ve made these bars numerous times in the past couple of months, we look love them! I always use double the berries. Very simple to make.
Beth, doubling the berries sounds like an excellent idea. I’m so glad to hear this recipe is a winner for you!
Could I use quick oats for this recipe?
Hi, I haven’t made it that way, so you’d be experimenting, but I think you could. I hope you enjoy the recipe!
Delicious and easy! Loved them. Lots of blueberries and not too sweet. Definitely a recipe I will use again.
YAY Lara, I’m so happy to hear you loved the bars. Thanks for giving them a try and sharing how it went!
These are so pretty, but I have to admit, my family thought they could be a bit sweeter. Especially when eating for dessert. Will just adjust that next time.
Kelly, these are definitely not super sweet (we eat them for breakfast), so I think more honey or maple syrup next time would do the trick!
Kelly, these are definitely not super super sweet, so feel free to adjust to your taste. Did you make the icing? That definitely sweetens them up too!
Made this recipe and loved it . I did add one egg as was concerned it may not hold together .
The icing on top provided the extra sweetness that my husband and guests like . For me it is perfect without it . Quick question – we need to avoid saturated fat and the jury is out on coconut oil (I did use it this time) & wondered whether light olive oil would work ok & not effect the flavour ? Or do you know of other good oil alternatives – perhaps Macadamia Nut oil – bit exxy though.
Linda, I am SO GLAD this was a hit! The texture of coconut oil in baking is different than olive oil, and its properties are different in baking, so this would definitely be an experiment on your part. My guess is the bars may turn out more soft/crumbly. That said, if it’s really important to you to use olive oil, you could experiment—I just can’t promise the results since I’ve never tried the recipe that way. If you do play around with the recipe, I’d love to hear how it comes out!!!
What an awesome recipe! The whole family loved these bars. So easy to make – the hardest part was waiting for the bars to cool before digging in! I might try adding some lemon zest into the glaze next time. Thank you so much for sharing this winner!!!
Erin, I am so so pleased to hear this! And the lemon zest sounds like a delicious addition!
Blueberries were on a mega sale at my store this week. I bought a flat of eight pints. Of course we’ll eat a lot of them on yogurt and cereal, but after making a blueberry orange loaf bread I wanted to do something different beyond muffins, crisp, cobbler, or pie. This recipe caught my eye.
Firstly, I want to say that I believe this recipe made exactly as directed would surely be very tasty. I know by the ingredients. But I did the usual minor modifications that many do, in my case to lower the sugar and net carb content since I’m watching my diet and sugar consumption.
I made the recipe with only the following changes:
1. I used Truvia Brown Sugar Baking Mix in place of the regular brown sugar. Half the amount provides the same sweetness as the full amount of regular brown sugar. However, it was my concern that the reduced amount of Truvia brown sugar mix might reduce the binding qualities and flavor, so I also added 2 tsp Black Strap molasses. A nice flavor boost for little extra sugar.
2. I reduced the all-purpose flour amount by 1/3 cup or so and made up the difference with finely ground walnuts. Mmmm! Walnuts. Especially after they toast a bit during the baking.
3. I reserved a little bit more than 1/2 cup oat topping for the top most level. I’m glad I did. The bottom crust was sufficiently thick ( I used the pan size recommended), and I felt the extra topping was necessary.
4. I used Swerve confectioner’s sugar substitute in place of regular confectioner’s sugar, and found I needed a bit more milk to thin it out to my liking. Next time, I’d probably drizzle it on after the bars chill in the fridge a bit in the pan, and then remove the uncut bars from the pan, lifting them out with the parchment paper arrangement.
Everything else I did exactly as the recipe said, including the butter amount. I did have to bake it a good 15 mins more, but my oven is slow. Both my husband and I think they are delicious. Mine are perhaps slightly sweeter than I’d like. I think the confectioner’s drizzle could be eliminated, though it is pretty. I really like the extra nutty flavor from the walnuts I added. What can I say? I love nuts! My adaptation is surely slightly higher in fat than the original, but lower in net carbs and refined sugar. I used regular white sugar for the blueberry sprinkling, but could have used Truvia, etc., to cut down refined sugar even more.
I found that the bars firm up perfectly as they cool, or particularly chill.
Elaine, I am so happy these bars turned out to be a yummy way to use those beautiful blueberries. Thanks for sharing this detailed review and enjoy! (and I love nuts too :) ).
Excited to try these out for the first time for my bookclub – any problem making it the night before and then popping it in the oven in the morning? Thanks!
Hi Shannon! I actually worry the batter would get too soft underneath. You could prep the crumble in advance, then store it in the refrigerator. I’d press it into the pan, then add the blueberries/second half of the crumble just before baking.
Thanks so much for the rec/advice!
I had these at a friends house and they were ahhhhh mazing! I’ve tried to make them twice and they just won’t set for me. It tastes delicious but no need to even cut because it’s so crumbly. Help!
Hi Tera, I’m so happy you enjoyed these bars at your friend’s house! I’m sorry you’ve had trouble trying to make them though, and I’m not sure what might be going wrong. Did you make any substitutions to the ingredients list? Another reader has mentioned that she mashes some of the blueberries first to help the bars bind together better, so that might help. I hope you still enjoyed the flavors!
This is my new favorite breakfast recipe! Easy, healthy, and so tasty. The only change I made was I combined the cornstarch and granulated sugar and tossed the berries in that first before adding them to the pan. My son was home from college and said they were the best bars I’ve made yet. Thank you for the recipe!
Janet, I am so so happy to hear these were a hit and your son enjoyed them too!
Love this recipe Thank you.
I am so glad to hear it Ruth, thank you!
So excited to try these!! How do you recommend thawing individual bars if we freeze them?
Hi Morgan! Overnight in the refrigerator.
My lemon squeezed more juice than expected… but I just went with it, and thought “what would Erin do?”… told everyone they were blueberry lemon bars. ;-) Delicious!
Excellent idea! :) I’m so glad you enjoyed these, Shannon.
Haven’t made these yet be cause i have dried blueberry’s so how can i use these for this recipe Help or Ideas Reply
Hi Martha, I developed and tested the recipe with fresh blueberries, so that’s the way I can vouch for the results. I have not tried using dried blueberries, but the recipe would come out very different. You may be able to reconstitute the berries first, but that would be an experiment. I’d recommend doing an online search for recipes using dried blueberries. If you do decide to try this recipe with fresh blueberries, I hope you enjoy it!
yo can someone tell me the serving size and cost per serving size of this recipe. thx
Hi Alex, the serving size is 1 bar (out of 16). The cost per serving will vary depending upon the ingredients you purchase.
Made this recipe with huckleberries and it was AMAZING!!!!
That sounds divine, Jessie! Thanks for reporting back!
These were wonderful! I made them both with fresh blueberries and then with frozen blueberries. In my personal opinion the bars with the fresh blueberries were better, they just had more flavor.
Jamie, I am SO pleased you liked these. Thanks for reporting back and sharing the fresh vs. frozen tip too!
Wow, these were fantastic! I made them with extra virgin olive oil and added lemon zest and they turned out great. I found that lemon zest in the crust as well as the blueberry mixture really made the flavours shine.
Thanks for sharing this review! I’m so happy to hear you enjoyed the muffins.
These are delicious but a little crazy that it says 16 bars in an 8″ by 8″ pan. So they’re 2″ by 2″ squares? That doesn’t sound like much of a breakfast. I cut them into 8 servings, they’re still small 4″ by 2″ rectangles.
Hi Amy, you can certainly cut the bars however big you’d like! I’m glad to hear you enjoy them.
I doubled the recipe but did 2 8×8, one with strawberries and one with blueberries, skipped the glaze but added caramel drops to half. Next time may try bananas and berries, double batch in 9×13 for thicker bars. All who tried them loved them!
I’m so happy to hear this, Emily! Thank you for sharing your success with this recipe!
I’m having a hard time getting my blueberries to burst and bubble. I’m not sure what is going on. They’ve been in the oven for 45 min. I’ll give you an update when I finish.
I think it is my oven acting up. They are turning out nice and bubbly now.
I’m happy to hear that these turned out well for you, Karie! Thank you for taking the time to share your success with the recipe!
I made these bars. They taste really good! The textures could be improved a little, though.
– I would suggest incorporating the cornstarch, sugar, and lemon juice with the blueberries before putting them in the pan, and smashing the blueberries a little bit so it turns more gooey when it cooks.
– The crumble part was a little too dry for me after I added the butter, so I added a squeeze of lemon juice which helped it come together.
Thank you for sharing your thoughts, Leah! I’m happy you loved the taste of these bars!
Great recipe! I was skeptical about the quantity of blueberries, but it works. I used regular, all purpose flour. Very easy, came out great. I sprinkled individual bars with confectioner sugar.
YAY! I’m so happy to hear that this recipe was a hit, Chris! Thank you for sharing this kind review!
YUMMMMMM – we loved these bars so much!
I’m so happy this recipe was a hit for you, Colleen! Thank you for taking the time to share this kind review!
These are definitely yummy and a nice healthy choice compared to chocolate chip cookies 😉
I would maybe add a little more butter to the crust to make it not as crumbly. I did end up baking it longer because it didn’t really toast up. But the flavors were great! They would be good with or without the icing
I’m so pleased that you enjoyed the recipe, Melanie! Thank you for sharing this kind review!
I made this recipe today while being socially isolated from the world due. I doubled the ingredients and added sugared coconut. I used blueberries I had picked and then frozen last year. I was a little generous with the ingredients and still did not have too much for a deep sided 9X13 pan. The blueberries came out like delicious blueberry jam even though the thawed frozen blueberries were mushy. The little bit of cornstarch is a must! I did not add a frosting on top and everyone thought the bars were sweet enough. The bars sliced beautifully and held together well. This recipe really deserves more stars. My family loved it!
Thank you for sharing this kind review, Mary! I’m SO pleased that you enjoyed the recipe!
Made the blueberry oatmeal bars this morning. Unfortunately, they fell apart when I tried to cut them into bars. I had to scoop them into bowls, instead. I used coconut oil. Do you think that’s why? I let them cool thoroughly.
Again, the taste was awesome. Just disappointed they couldn’t be cut into bars.
Hi BJ! I’m sorry to hear that these didn’t hold up well. I’m not sure what might’ve gone wrong, but I don’t think it would be caused by the coconut oil. Another reader has mentioned that she mashes some of the blueberries first to help the bars bind together better, so that might help. I’m so happy you still enjoyed the flavor!
My did not hold together well. Used all exact ingredients and measurements. Also there were tiny bits of cornstarch here and there. They were delicious though.
Hi Debbie! I’m sorry to hear that these didn’t hold up well. Another reader mentioned that she mashes some of the blueberries first to help the bars bind together better, so that might help. I’m so happy you still were able to enjoy them!
Delicious! I made this with blueberries that I had in my freezer since last summer (completely thawed first). Thank you for this recipe!
Thank you for taking the time to share this kind review, Chris! I’m so pleased that you enjoyed the recipe!
I added some crushed up almonds & coconut 😋
I’m so pleased that you enjoyed the recipe, APS! Thank you for sharing this kind review!
Erin does it again! These turned out SO good both times we’ve made them. We never got the golden brown color on the top and were worried that we were pulling it out of the oven too soon, but 40 min was perfect and these are major crowd pleasers!
I’m so pleased that you enjoyed them, Lauren! Thank you for sharing this kind review!
I have made both the strawberry and blueberry bars. Both are so delicious! They last about 8 hours in my house. I do not personally use the glaze but I bet it’s amazing also.
Thanks for such an amazing recipe!
I’m so happy that you’ve enjoyed the bars, Stephanie! Thank you for sharing this kind review!
Made once and have another batch in oven. Very flavorful and great textures. I added a cup of toasted sliced almonds and half cup of unsweetened coconut. The mixture was a bit dry because of the added dry ingredients so added an egg and it all came together nicely. Even though low in sugar, I cut down to 1/4 cup and no one complained:-). Thanks for great healthy bar recipe!!
I’m so happy that you enjoyed them, Marcie! Thank you for sharing this kind review!