Ultimate Baked Cheesy Brussels Sprouts Casserole

This Ultimate Baked Cheesy Brussels Sprouts Casserole is creamy, comforting, and loaded with melted cheese. Perfect for weeknight dinners, Thanksgiving sides, or any holiday meal — it’s a cozy favorite everyone will love.

Prep Time20

Cook Time30

Total Time50

Course: Side Dish

Cuisine: American

Keyword: baked Brussels sprouts, Brussels sprouts with cheese, cheesy Brussels sprouts casserole, cheesy vegetable casserole, comfort food side dish, creamy Brussels sprouts recipe, Easy Holiday Side Dish, oven baked casserole recipe, Thanksgiving Brussels sprouts, weeknight dinner side

Servings: servings

Calories: 449kcal

Author: George - U Keep Cooking

Equipment

1 9 x 13 baking dish

Ingredients

2 lbs Brussels sprouts (trimmed and thinly sliced (about 8 cups))
8 slices bacon (cooked until crisp and crumbled (reserve 1–2 Tbsp drippings))
1 Tbsp olive oil (only if you need extra fat after reserving bacon drippings)
1 onion (finely chopped)
3 cloves garlic (minced)
½ tsp salt (start here — bacon adds salt, taste and adjust)
½ tsp black pepper
½ tsp crushed red pepper flakes (optional)

Custard Filling:

3 eggs
1 cup heavy cream
1 cup Sharp cheddar cheese (shredded)(plus ¼ cup for topping)
1 cup Gruyère cheese (shredded)
½ cup Parmesan cheese (grated)

Crispy Topping:

½ cup panko breadcrumbs
2 Tbsp butter (melted)

Instructions

Preheat & prep: Preheat oven to 375°F. Lightly grease a 9x13-inch baking dish.
Cook the bacon: In a large skillet, cook bacon until crisp. Move bacon to paper towels to drain, then crumble. Pour off all but 1–2 Tbsp of the bacon drippings into the skillet (save the rest or discard). If you don’t have enough fat left, add 1 Tbsp olive oil.
Sauté aromatics & sprouts: Over medium heat, add the chopped onion to the skillet and cook until soft, about 5 minutes. Stir in the garlic for 1 minute. Add the sliced Brussels sprouts and a pinch of salt; sauté 6–8 minutes until they’re just tender (they should still have some bite).
Mix the custard: In a large bowl whisk the eggs, half-and-half, Parmesan, ½ tsp salt, black pepper, and red pepper flakes. Stir in the shredded cheddar and Gruyère.
Combine: Fold the cooked Brussels sprouts and about half of the crumbled bacon into the egg-cheese mixture. Pour everything into the prepared baking dish.
Top & bake: Mix panko with the melted butter and sprinkle evenly over the casserole. Top with the remaining ¼ cup cheddar and the rest of the crumbled bacon. Bake 25–30 minutes until golden and set in the center.
Rest & serve: Let rest 5 minutes before serving. I like to finish with a little extra cracked pepper or fresh parsley if I have it.

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