Preheat oven to 350 degrees (if making the casserole day of).
In a large frying pan, cook sausage until brown. Drain and set aside.
In same frying pan, lightly brown hash browns (if your skillet is on the smaller side, you may want to do this in two separate batches), then place hash browns into a greased 9x13 casserole dish. Top with sausage and cheese.
In a medium bowl, whisk eggs, milk, and all spices until combined. Pour over casserole mixture.
Cover casserole dish with aluminum foil and place in the refrigerator overnight.
Bake uncovered at 350 degrees for 40 minutes or until cheese starts to bubble and brown and top.