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.)
Nutrition
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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!
I just made this and waiting for it to cool. Can’t wait to try. I used fresh blueberries from my blueberry bush. I took a picture of it and will share your link on my site.
Thank you for sharing
Sandy, I’m so happy you found this recipe and hope you love the bars!
This is amazing! Fresh Michigan blueberries at their finest and my husband, who doesn’t like blueberries, won’t stop eating it. Perfect recipe as always!!!
I’m so happy that the bars were a hit, Donna! Thank you for sharing this kind review!
Really, really delicious. We are in hardcore lockdown in near freezing temperatures (we are at the bottom of Australia) and were looking for something to brighten our day, so we made these. They taste like blueberry pie. Yum yum yum.
Diane, I am so so pleased to hear it! Thanks for taking time to share this lovely review!
These looked delish and I had just taken my kiddos to the blueberry patch. These did NOT disappoint. I didn’t want to use that much butter in these as I was looking for a healthy breakfast/dessert option for everyone.
I replaced the whole wheat flour with almond flour. I also replaced 6 tbsp with 4 tbsp of mashed banana and 2 tbsp of coconut oil. The “crust” was more of a…base. They were soft because of the banana. I’m totally okay with that though.
I had one for breakfast with a dollop of plain greek yogurt. Woah.
My hubby had some with a bit of ice cream that night.
Y’all, I didn’t even make the glaze.
I’m SO happy that you enjoyed them, Christie! Thank you for sharing this kind review and your adaptations!
These are so pretty! I have a huge bag of aronia berries…thoughts on substituting those for the blueberries?
Hi Stacy! I’ve only tested this recipe with blueberries, but you could experiment with them. If you decide to try it, I’d love to hear how it goes!
I have been making these for over a year. I have three kids and run a home daycare. These are everyone’s favourite. I make them with frozen berries because I always have them and we skip the icing on top (usually!). Just wanted to let you know how much we love them!
I’m so happy that you’ve enjoyed them, Meg! Thank you for sharing this kind review!
We made this today but wasn’t firm enough to be cut, fell apart. But tasted good!
I’m happy that you enjoyed the flavor of the bars, Barb! Thank you for trying the recipe!
I used frozen blueberries and can confirm they turned out great, just took a little longer to bake. Thanks for the recipe!
I’m so happy that you enjoyed the recipe! Thank you for sharing this kind review!
These bars are blueberry heaven! Sooo good, bit chewy, not at all dry and tons of blueberries in every bite. Didn’t make the glaze but I can imagine it would be fantastic. Followed recipe using whole wheat pastry flour but added pinch more cinnamon, 1/2t ginger and 1/4t nutmeg.
I’m so happy that you enjoyed it, Debs! Thank you for sharing this kind review!
Thank you! I love this recipe! I did not add the icing! I used defrosted blueberries and may smash them down next time! I added it to yogurt and it’s delicious as a dessert!
I’m so happy that you enjoyed them, Lynn! Thank you for sharing this kind review!