Preheat your oven to 375°F (190°C) to prepare for baking the casserole.
Heat a large skillet over medium heat. Add the breakfast sausage and cook, breaking it apart with a spatula, until it is well browned and cooked through. Once done, remove the skillet from the heat, allowing it to cool slightly, then drain off any excess fat.
Using the same skillet, add the diced onion and red bell pepper. Sauté the vegetables for about 3-4 minutes or until they become softened and fragrant, stirring occasionally to ensure even cooking.
In a large mixing bowl, combine the cooked sausage, sautéed onion, and bell pepper with the thawed hash browns. Stir in half of the shredded cheddar cheese until all ingredients are evenly mixed.
In a separate bowl, whisk together the eggs, milk, garlic powder, onion powder, salt, and pepper until smooth and fully combined, ensuring a fluffy texture.
Grease a 9x13-inch baking dish with non-stick cooking spray or butter. Spread the sausage and hash brown mixture evenly across the bottom of the dish. Carefully pour the egg mixture over the top, making sure it seeps through the hash browns. Finish by sprinkling the remaining cheddar cheese evenly across the surface.
Place the casserole in the preheated oven and bake for 30-35 minutes, or until the egg is set in the center and the top has turned a lovely golden brown.
Allow the casserole to cool for a few minutes after baking. Slice it into squares and garnish with freshly chopped parsley for an appealing touch of color.
Notes
Serve with fresh fruit salad or sliced avocado for a balanced meal.