Preheat oven to 350°F (180°C). Grease a 9x13-inch baking dish and set aside.
Brown the sausage in a skillet; drain.
While the sausage cooks, prepare the egg mixture. In a large bowl, whisk together eggs, milk, ½ teaspoon salt, onion powder and garlic powder. Set aside.
In the prepared baking dish, combine hash brown potatoes, cooked sausage, 1 cup of cheese and remaining ½ teaspoon salt. Pour egg mixture over top.
Sprinkle remaining 1 cup of cheese over top. Cover tightly with foil.
Bake for 50 minutes. Remove foil and bake for another 10-15 minutes, or until knife inserted in center comes out clean. Let stand for 5-10 minutes before serving.