Preheat your oven to 350°F (175°C).
Grease the baking dish with cooking spray or butter.
In a large mixing bowl, combine the frozen hash browns, diced ham or sausage, bell peppers, onion, garlic powder, paprika, salt, and pepper. Mix well.
Spread the hash brown mixture evenly in the bottom of the prepared baking dish.
In another bowl, whisk together the eggs and milk until well combined. Season with additional salt and pepper if desired.
Pour the egg mixture over the hash browns in the baking dish, ensuring even coverage.
Sprinkle the shredded cheddar cheese evenly on top of the casserole.
Bake in the preheated oven for 45 minutes, or until the eggs are set and the top is golden brown.
Remove from the oven and let sit for 5 minutes before slicing.
Serve warm and enjoy!