Creating the Croissant Breakfast Casserole is straightforward if you follow these easy steps:

1. Preheat Oven: Preheat your oven to 350°F (175°C) and grease a 9×13-inch baking dish.
2. Prepare Croissants: Cut the croissants into bite-sized pieces and place them evenly in the greased baking dish.
3. Cook Meat (if using): In a skillet, cook the sausage or bacon until browned. Drain excess fat and sprinkle it over the croissant pieces.
4. Add Vegetables (optional): If using, add the chopped bell peppers and onions over the croissants and meat.
5. Whisk Eggs: In a mixing bowl, whisk together the eggs, milk, garlic powder, salt, and black pepper until well combined.
6. Pour Mixture: Carefully pour the egg mixture over the croissant and meat layers in the baking dish.
7. Add Cheese: Sprinkle the shredded cheddar cheese evenly over the top.
8. Chill (optional): For best results, cover the dish with foil and refrigerate for at least 1 hour. This allows the croissants to soak up the egg mixture.
9. Bake: Remove the foil and bake in the preheated oven for 30-35 minutes, or until the eggs are set and the top is golden brown.
10. Cool Slightly: Allow the casserole to cool for a few minutes before slicing.
11. Garnish: If desired, sprinkle fresh herbs on top for added flavor and presentation.

Following these steps will guide you in creating this incredible breakfast casserole effortlessly.