Broccoli Casserole - Nasiff Marketplace

Ingredients

• 2½ pounds broccoli florets, cut into bite-size pieces (about 10 cups)
• 6 tablespoons butter, divided
• 1 cup finely chopped cremini mushrooms
• 1 cup finely chopped yellow onion
• ¼ cup flour
• 1 cup milk, whole or 2% preferred
• ½ cup half and half
• ½ teaspoon salt
• ¼ teaspoon freshly ground black pepper
• ½ cup plain Greek yogurt*, full fat or 2%
• 1 egg, lightly beaten
• 1½ cups grated cheddar cheese, divided
• 1¼ cups whole-wheat breadcrumbs, homemade* or store-bought, divided