Creamy Parmesan Brussels Sprouts Casserole (Print Version)
Tender Brussels sprouts in a creamy Parmesan sauce, baked until golden and bubbly.
# What You'll Need:
→ Vegetables
01 - 1½ lbs Brussels sprouts, trimmed and halved
02 - 1 medium yellow onion, finely chopped
03 - 2 cloves garlic, minced
→ Sauce
04 - 2 tbsp unsalted butter
05 - 2 tbsp all-purpose flour
06 - 1½ cups whole milk
07 - 1 cup heavy cream
08 - 1 tsp Dijon mustard
09 - ½ tsp black pepper
10 - ½ tsp salt
11 - ¼ tsp ground nutmeg
→ Cheese
12 - 1¼ cups grated Parmesan cheese, divided
13 - 1 cup shredded mozzarella cheese
→ Topping
14 - ½ cup panko breadcrumbs
15 - 1 tbsp olive oil
16 - 2 tbsp chopped fresh parsley
# Steps:
01 - Preheat oven to 400°F. Lightly grease a 9x13-inch casserole dish with butter or non-stick spray.
02 - Bring a large pot of generously salted water to a rolling boil. Add the trimmed and halved Brussels sprouts, cooking for 3 to 4 minutes until just fork-tender. Drain thoroughly and set aside.
03 - In a large skillet over medium heat, melt the butter. Add the finely chopped onion and cook until softened and translucent, about 3 minutes. Stir in the minced garlic and cook for an additional 30 seconds until fragrant.
04 - Sprinkle the flour over the onion and garlic mixture. Stir continuously and cook for 1 to 2 minutes to form a smooth roux, removing any raw flour taste.
05 - Gradually whisk in the whole milk and heavy cream, pouring slowly to prevent lumps. Continue whisking over medium heat until the sauce thickens and coats the back of a spoon, approximately 4 minutes. Season with Dijon mustard, salt, black pepper, and ground nutmeg.
06 - Remove the skillet from heat. Add ¾ cup of the Parmesan cheese and all of the mozzarella cheese, stirring gently until fully melted and the sauce is smooth and glossy.
07 - Add the blanched Brussels sprouts to the skillet, tossing to coat evenly with the creamy cheese sauce. Transfer the entire mixture to the prepared casserole dish, spreading into an even layer. Sprinkle the remaining ½ cup Parmesan cheese evenly over the top.
08 - In a small bowl, toss the panko breadcrumbs with olive oil until evenly coated. Sprinkle the seasoned panko over the casserole in a uniform layer.
09 - Bake in the preheated oven for 25 to 30 minutes, or until the top is deeply golden and the edges are bubbling. Remove from oven and allow the casserole to rest for 5 minutes.
10 - Sprinkle chopped fresh parsley over the top just before serving. Serve hot as a standalone vegetarian entrée or as a comforting side dish.
# Expert Tips:
01 -
- The creamy Parmesan sauce converts even the most stubborn Brussels sprout skeptics at your table.
- It reheats beautifully the next day, making it ideal for prepping ahead when you have guests coming.
02 -
- Do not skip the blanching step because raw sprouts will not cook through properly in the oven and you will end up with tough centers.
- Add the cheese off the heat or it can separate and turn grainy instead of smooth.
03 -
- Cut all your Brussels sprouts in half so more surface area gets coated in sauce and caramelizes in the oven.
- Let the casserole rest those 5 minutes before serving because the sauce thickens as it cools and holds together better on the plate.