Follow these simple steps to create your Cheesy Breakfast Casserole:

1. Preheat the Oven: Begin by preheating your oven to 350°F (175°C).
2. Prepare the Baking Dish: Grease a 9×13-inch baking dish with cooking spray or butter.
3. Cube the Bread: Cut your loaf of bread into bite-sized cubes and spread them evenly in the prepared baking dish.
4. Cook the Meat: If using sausage or bacon, cook it in a skillet over medium heat until browned. Drain excess fat and sprinkle over the bread cubes.
5. Add Vegetables: If desired, sauté bell peppers and onions until soft. Add them to the baking dish.
6. Whisk Eggs and Milk: In a large bowl, whisk together the eggs, milk, salt, black pepper, garlic powder, and paprika until well combined.
7. Add Cheese: Stir in 1 ½ cups of shredded cheese into the egg mixture.
8. Pour the Mixture: Pour the egg and cheese mixture over the bread cubes and other ingredients in the baking dish, ensuring even coverage.
9. Sprinkle Remaining Cheese: Top with the remaining cheese for a melty finish.
10. Bake: Place the casserole in the preheated oven and bake for 45 minutes, or until the eggs are set and the cheese is bubbly and golden.
11. Cool and Serve: Allow the casserole to cool for a few minutes before slicing into squares.

These steps will guide you through the preparation of your delicious Cheesy Breakfast Casserole with ease.