Preheat oven to 375°F (If you plan to cook it now). I
In a large skillet, cook sausage until no longer pink. Drain fat.
Add hash browns the bottom of lightly greased 7x11-inch baking pan. Top with sausage.
Whisk cream cheese until smooth. Whisk in the eggs and beat until well blended. Add the seasonings and milk and beat until frothy. Pour over the hashbrown and sausage.
Cover and refrigerate if you're baking it later.
If baking now, place in a 375°F preheated oven, uncovered. Bake for 30 to 35 minutes until heated cooked throughout and the cheese has melted.
Allow the casserole to sit and cool 5 minutes before cutting and serving.
Notes
You can make this casserole ahead of time and refrigerate overnight. As well, you can freeze it for later.To bake after freezing, thaw completely in the refrigerator and bake as directed.