Brussels Sprouts Gratin
If you have any lingering vegetable skeptics in your family, try gratin-ing them. Plain old Brussels sprouts? They’re a hard sell to any non-veggie lover, especially at the holidays when decadent dishes command the attention on the plate. Brussels Sprouts Gratin (a.k.a. Brussels sprouts covered in a bubbly, creamy sauce and coating of buttery, crispy bread crumbs)? Use the big serving spoon!
Gratins or au gratin or, if we are being REALLY fancy, gratinée are catch-all terms for something (usually vegetables) baked in a shallow dish (often called a gratin dish) with a lid of cheesy, crispy something (usually breadcrumbs and Gruyère cheese) baked on top. Does this sound familiar?
Gratins are a casserole. We are making a cheesy Brussels sprouts casserole. With bacon.
Let’s keep calling it a gratin though, can we please? I like to feel a little fancy at the holidays, and “gratin” definitely sounds fancy.
Calling this recipe Brussels Sprouts Gratin also makes it seem a lot more complicated to make than it actually is.
Since I already leveled with you that “Brussels sprouts au gratin with bacon” is just a deluxe way of saying “Brussels sprouts casserole with bacon,” I might as well complete the exposé by stating declaratively that it is not difficult at all.
This is an easy Brussels sprouts gratin recipe that will impress your family. There are a number of steps, but each is straightforward. I have total confidence that you can pull it off with style.
Why I Love This Healthy Brussels Sprouts Gratin
When I was growing up, most of my family’s holiday spreads were conspicuously heavy on the white/yellow side dishes and missing in the green…unless you count the lime Jell-O salad. If you grew up in the Midwest, you know the one.
Today, some members of my family are still a little hesitant to embrace the green (Asian Ramen Salad not withstanding), but we’ve slowly been adding more vegetables here and there.
While Roasted Frozen Brussels Sprouts, Oven Roasted Brussels Sprouts, or Roasted Brussels Sprouts with Garlic and Parmesan would be a tough sell, I’m confident that today’s Brussels Sprouts Gratin will be granted universal approval. Homemade Scalloped Potatoes (which are sort of like a casserole/gratin) are a fixture at our holiday feasts, so this Brussels Sprouts Gratin should be an easy transition.
Make Ahead Tips
- To Make Ahead. Prepare the dish through step 3 up to 1 day in advance and store covered in the refrigerator.
- When ready to bake, sprinkle with bread crumbs and bacon.
More Tasty Holiday Side Dishes
- Smashed Brussels Sprouts
- Brussels Sprouts Slaw
- Broccoli Rice Casserole
- Cauliflower Casserole
- You can also check out the many Healthy Thanksgiving Sides on my site!
In keeping with my usual recipe approach, this Brussels sprouts casserole is healthy (well, healthier than most), but I promise that between the Gruyère cheese, crispy bread crumb topping, and BACON, you and your guests won’t notice the lighter tweaks one bit.
Brussel Sprouts Gratin
- 3 slices thick-cut bacon
- 2 pounds brussels sprouts - trimmed and halved (cut into thirds or quarters if very large—you want the pieces to be roughly the same size)
- 1/2 yellow onion - finely diced
- 3/4 teaspoon kosher salt - divided
- 1 tablespoon unsalted butter
- 2 tablespoons all-purpose flour
- 1 1/2 cups 2% milk
- 1 tablespoon chopped fresh thyme - or 1 teaspoon dried thyme leaves
- 1/4 teaspoon black pepper
- Pinch ground nutmeg - optional
- 1/2 cup freshly grated Gruyère cheese - sharp white cheddar cheese, or a similar fully flavored, melty cheese
- 1/4 cup whole wheat bread crumbs
- Olive oil cooking spray
- Preheat the oven to 400 degrees F. Lightly coat an 8x12-inch or similar 2-quart glass or ceramic gratin or casserole dish with olive oil cooking spray. Set aside.
- In a large frying pan, cook the bacon over medium-low heat until crisp, about 8 to 10 minutes. (Do not rush it or the bacon will burn before it is fully crispy.) Remove the bacon to a paper-towel-lined plate, pat dry, and let cool. Discard all but 1 tablespoon of the bacon drippings from the pan.
- Place the pan back on the heat and increase the heat to medium high. Add brussels sprouts, onions, and 1/2 teaspoon kosher salt. Stir and cook until the onion is soft and golden and the brussels sprouts are crisp-tender, about 10 to 12 minutes. Add 1/2 cup water. Bring to a boil, then cook until the liquid is evaporated, about 2 to 3 minutes. Spoon the brussels sprouts and onions into the prepared baking dish. Carefully wipe the pan clean.
- Melt the butter in the pan over medium. Once melted, sprinkle the flour over the top and whisk until the flour becomes golden, about 1 minute. Add the milk a few splashes at a time, whisking vigorously as you go to break up any lumps. Once all the milk is added, bring the mixture to a simmer. Continue to simmer, stirring often, until the mixture thickens into a sauce, about 2 to 4 additional minutes. Stir in the thyme, pepper, nutmeg, and remaining 1/4 teaspoon salt. Remove the pan from the heat and stir in the cheese until it melts. Taste and add additional salt or pepper as desired (remember that the bacon will also add some saltiness). Pour over the brussels sprouts, and with a spatula or the back of a spoon, spread the sauce evenly over the top.
- Sprinkle the bread crumbs over the top of the brussels sprouts, then lightly coat the breadcrumbs with olive oil spray. Crumble the bacon, then sprinkle it over the top. Place in the oven and bake until hot and bubbly and the bread crumbs are golden, about 10 to 15 minutes. Serve hot.
- Prepare the dish through step 3 up to 1 day in advance and store covered in the refrigerator. Sprinkle with bread crumbs and bacon just prior to baking.
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