Creamy Parmesan Brussels Sprouts Casserole (Printable Version)
Tender Brussels sprouts in a creamy Parmesan sauce, baked until golden and bubbly. A rich, comforting side perfect for holidays or everyday meals.
# What You Need:
→ Vegetables
01 - 1½ lbs Brussels sprouts, trimmed and halved
02 - 1 medium yellow onion, finely chopped
03 - 2 cloves garlic, minced
→ Cream 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
# How To Make:
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 chopped onion and cook for about 3 minutes until softened and translucent. 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 for about 4 minutes until the sauce thickens and coats the back of a spoon. Stir in the 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 completely melted and the sauce is smooth.
07 - Add the blanched Brussels sprouts to the skillet, tossing to coat evenly in the creamy cheese sauce. Transfer the entire mixture to the prepared casserole dish, spreading into an even layer.
08 - Sprinkle the remaining ½ cup of Parmesan cheese evenly over the top. In a small bowl, toss the panko breadcrumbs with olive oil and scatter over the casserole for a golden, crunchy finish.
09 - Bake in the preheated oven for 25 to 30 minutes until the top is golden brown and the sauce is bubbling around the edges.
10 - Remove from the oven and let the casserole rest for 5 minutes to set. Garnish with chopped fresh parsley and serve hot.
# Expert Advice:
01 -
- The creamy Parmesan sauce turns even the most stubborn Brussels sprout skeptic into a fan.
- It reheats beautifully the next day, making it ideal for meal prep or leftover lunches.
02 -
- Do not skip blanching the sprouts, as raw ones will not cook through properly in the oven and you will end up with tough, chewy centers.
- Adding cheese off the heat prevents the sauce from breaking and turning grainy, a lesson I learned after one gritty batch.
03 -
- Cut all the sprouts in half so they sit cut side down in the dish, which creates more surface area for that golden, caramelized top.
- Toss the panko with a pinch of garlic powder and a little extra Parmesan before sprinkling it on for a topping that people will fight over.