Preheat the oven to 350F. Spray casserole dish with nonstick spray.
In a large skillet, cook the sausage until no longer pink, drain if desired.
In a small bowl, whisk together milk and eggs.
In a large mixing bowl, combine the cooked sausage, hash browns, 1 cup of cheddar cheese, sour cream, onion powder, garlic powder, salt, pepper. And milk mixture.
Mix to combine.
Spread evenly in the casserole dish. Top with remaining shredded cheese.
Bake uncovered for 30 minutes or until the cheese is melted and the casserole is bubbly.
Remove from oven and garnish with parsley or green onions if desired. Enjoy!