Preheat your oven to 350°F (175°C) and grease a 9x13-inch baking dish with cooking spray.
In a large skillet over medium heat, add the breakfast sausage. Cook until browned, breaking it up with a spatula as it cooks. Add the chopped onion and red bell pepper, cooking until the veggies are softened, about 5 minutes.
In a mixing bowl, whisk together the eggs, half and half, green chilis, 1 teaspoon of salt, ½ teaspoon of black pepper, and garlic powder until well combined.
In the prepared baking dish, layer the thawed hash browns evenly. Next, spread the sausage and vegetable mixture over the hash browns. Pour the egg mixture over everything, ensuring it’s evenly distributed.
Sprinkle the shredded cheddar cheese on top of the casserole, allowing it to melt and create a delicious crust.
Bake in the preheated oven for 45-50 minutes, or until the center is set and a knife inserted comes out clean. Let it cool for a few minutes before serving.
Garnish with sliced scallions for a fresh touch, and serve hot.
