Butter a 9x13-inch baking dish. Cut and fit 8 slices of bread to fit over entire bottom of dish. Cover bread with slices of Canadian bacon and sharp Cheddar cheese. Cut and fit remaining 8 slices of bread to completely cover bacon and cheese.
Whisk eggs with salt and black pepper in a bowl. Whisk dry mustard, onion, diced green and red bell pepper, Worcestershire sauce, and hot sauce into eggs. Whisk in milk until egg mixture is smoothly combined. Pour egg mixture evenly over the casserole. Cover the dish and refrigerate overnight.
Preheat oven to 350 degrees F (175 degrees C).
Pour melted butter evenly over the casserole and sprinkle corn flake crumbs over the top.
Bake in the preheated oven until set and lightly browned, about 1 hour. Let casserole stand for 10 minutes before serving.