Creamy Baked Parmesan Broccoli Casserole

Instructions

1. 1

   Preheat the oven to 400°F. Steam the broccoli florets in batches until crisp-tender, about 3-4 minutes per batch. Transfer the steamed broccoli to a greased 13x9-inch baking dish.

2. 2

   In a small saucepan, melt 4 tablespoons of butter over medium heat. Add the chopped onion and cook until tender, about 5 minutes. Stir in the minced garlic and cook for 1 minute more.

3. 3

   Whisk in the all-purpose flour until blended, then gradually add the milk. Bring the mixture to a boil and cook, stirring constantly, until thickened, about 2 minutes. Remove from heat and stir in a small amount of the hot mixture into the beaten egg yolk, then return the egg mixture to the saucepan, stirring constantly. Cook for 1 minute more, then stir in the Parmesan cheese, salt, and pepper.

4. 4

   Pour the cheese sauce over the broccoli in the baking dish, spreading it evenly.

5. 5

   In a small skillet, melt the remaining 2 tablespoons of butter over medium heat. Add the breadcrumbs and cook, stirring frequently, until golden brown. Sprinkle the toasted breadcrumbs over the top of the broccoli casserole.

6. 6

   Bake the casserole, uncovered, for 15-18 minutes, or until heated through and the breadcrumbs are crispy.