Brussels Sprouts Au Gratin is a new way you can prepare Brussels sprouts. Fresh Brussels sprouts are baked in a creamy cheese sauce with crispy bacon.
This post contains affiliate links. As an Amazon Associate, I earn from qualifying purchases.
Table of Contents
What Makes Brussels Sprouts Au Gratin a Side Dish That Needs To Be On Your Table
Sure, go ahead and make jokes about brussels sprouts. Turn your nose up at them if you wish, but you’ll miss out on one of the most delicious and versatile side dishes you can make.
If you are not already a fan of this much-maligned vegetable, then this Brussels Sprouts Au Gratin recipe is likely to change your mind. Not only is it deliciously hot and creamy, but it is also pretty nutritious!
What Makes This Recipe So Good?
Everything is better with bacon! Adding bacon to this dish delivers a subtle smoky taste that perfectly complements the earthy flavors in the brussels sprouts.
When combined with the slight nuttiness of a young gruyère cheese and the creaminess of the bechamel sauce, you wind up with a very special au gratin.
Ingredients For Au Gratin Brussels Sprouts
To prepare this dish, you’ll need:
- Fresh brussels sprouts
- All-purpose flour
- Whole milk
- Ground black pepper
- Gruyere cheese
- Bacon, cooked
Use a young gruyere in this recipe since less-aged gruyeres have a creamier texture and a slightly nutty flavor profile. Older gruyeres tend to have more earthy notes.
For the smoothest and creamiest sauce, it is best to grate the cheese yourself using a fine-hole grater. Manufacturers usually use an anti-caking additive to keep their pre-shredded cheeses from clumping. This additive also prevents the cheese from melting easily, which can be problematic in this recipe.
How To Make This Brussels Sprouts Casserole
To prepare the creamiest, crunchiest brussels sprouts that you have ever had:
- Preheat the oven to 350°F.
- Rough chop the cooked bacon.
- Remove any withered or discolored outer leaves from the brussels sprouts and rinse them well. Pat the brussels sprouts dry with a kitchen towel.
- Trim off the tough stem but don’t remove so much that the leaves start to separate.
- Cut the brussels sprouts in half longways.
- Dump the prepped brussels sprouts into a 9×13 casserole dish and shake them into a single layer. Set aside for later.
- Melt the butter in a saucepan over medium heat.
- Sprinkle the flour into the pan while whisking well. Continue to whisk and let the butter and flour mixture cook for about a minute until it is a light tan and smells like baked pie dough.
- Slowly pour in the milk and stir until the sauce thickens slightly.
- Season with salt and fresh pepper.
- Stir in the cheese in batches until it melts and the sauce is smooth.
- Pour the cheese sauce over the brussels sprouts in the casserole dish.
- Sprinkle the bacon on top.
- Put the dish in the oven and bake for 45 minutes, rotating the pan halfway through to ensure even cooking.
- Remove the casserole from the oven and allow it to cool slightly before serving.
Brussels Sprouts Au Gratin Recipe Variations
Feel free to customize this recipe depending on your tastes and what ingredients you have available. Here are a few suggestions you may want to try:
- Replacing gruyere with gouda for an extra boost of smokiness in the dish.
- Add a couple of tablespoons of parmesan cheese to the sauce.
- Sauteing a couple of tablespoons of minced shallots in the butter before adding the flour to add a new layer of flavor.
- Substituting cooked sausage or pancetta for the bacon.
What To Serve With Brussels Sprout Casserole
This is a wonderful side for any roasted meat or poultry dish. Serve it with steak or even as an appetizer with plenty of toasted bread.
How To Store the Leftovers
Let any extra au gratin brussels sprouts cool to room temperature before storing them in an airtight container for up five days in the refrigerator. While you can freeze leftovers, since this dish contains a dairy-based sauce, it may separate slightly once reheated.
What’s the Best Way to Reheat Brussels Sprout Casserole
To reheat thawed brussels sprouts gratin:
- Preheat the oven to 350°F.
- Set the Brussels Sprouts Au Gratin on the counter for at least ten minutes to eliminate some of the chill from the fridge.
- Cut the casserole into portions and place them in a clean baking dish.
- Cover the baking dish with aluminum foil and bake for about 25 minutes or until the casserole is warmed through.
Love Easy Oven Baked Side Dishes? Check Out These Recipes
- Baked Beans with Bacon
- Baked Potato Casserole
- Baked Red Potatoes Recipe
- Cheddar Cauliflower Recipe
- Creamed Corn Au Gratin
- Green Beans Gratin
- Keto Cauliflower Bake
- Keto Cheesy Broccoli
- Potatoes and Leeks Recipe
- Sweet Potatoes with Candied Pecans
More Brussels Sprouts Recipes
- Air Fryer Brussel Sprouts with Balsamic Glaze
- Crispy Brussel Sprouts with Bacon
- Roasted Brussel Sprouts
Brussels Sprouts Au Gratin
- 2 pounds fresh Brussels sprouts washed, trimmed, and halved
- 3 tablespoons butter
- 3 tablespoons all-purpose flour
- 2 1/2 cups whole milk
- 1/2 teaspoon salt
- 1/2 teaspoon ground black pepper
- 1 cup shredded Gruyère cheese
- 1/2 cup diced bacon cooked until crisp
- Preheat the oven to 350°F.
- Place the Brussels sprouts into a 9×13-inch baking dish.
- Melt the butter in a medium saucepan over medium heat. Add the flour. Whisk and continue to cook for about 1 minute. The butter and flour mixture will become fragrant like pie dough.
- Slowly add the milk and continue to whisk. When all the milk has been incorporated, cook until the sauce thickens, stirring constantly. Season with salt and pepper.
- Slowly add the cheese and stir to incorporate. Cook until the cheese has fully melted.
- Pour the cheese sauce over the Brussels sprouts, sprinkle the bacon on top, and bake in the preheated oven for about 45 minutes.