Preheat your oven to 450 degrees Fahrenheit.
Place the prepared brussels sprouts in a 2 quart baking dish and cover with aluminum foil. Roast the sprouts, covered, for 30 minutes, tossing them half way through.
1 1/2 pounds Brussels sprouts
While the sprouts are roasting, mix together the condensed soup, eggs, 1 cup of mozzarella cheese, milk, onion powder, garlic powder, salt, and pepper in a small bowl.
10.5 ounces condensed cream of mushroom soup, 2 eggs , 1 3/4 cups mozzarella cheese, 1/4 cup milk, 1 teaspoon onion powder, 1 teaspoon garlic powder, 1/2 teaspoon kosher salt, 1/4 teaspoon pepper
Reduce the oven to 350 degrees Fahrenheit.
Pour the mixture over the roasted Brussels sprouts. Toss to combine in the casserole dish. Top with 3/4 cup mozzarella cheese and the bread crumbs.
1 3/4 cups mozzarella cheese, 1/4 cup bread crumbs
Bake the casserole for 15 minutes, uncovered. To brown the cheese and crisp the breadcrumbs, broil for 1 to 2 minutes, watching very closely so it does not burn. Let the casserole sit for 5 minutes before serving.