Preheat oven to 350°F (175°C). Grease a 9x13-inch baking dish with nonstick spray.
Spread the thawed hash browns evenly in the bottom of the prepared dish.
Sprinkle the cheddar cheese, diced onions, and cooked bacon over the top of the hash browns.
In a large bowl, whisk together eggs, milk, salt, pepper, garlic powder, and paprika.
Pour the egg mixture evenly over the hash brown mixture.
Bake uncovered for 45–50 minutes, or until the eggs are set and the top is golden.
Let cool for 5–10 minutes before slicing and serving.