Pour hashbrowns into a large mixing bowl.
Spread sour cream and cream of mushroom soup over hashbrowns. Season with salt and pepper by sprinkling over the top. Stir well.
Add 2 cups of cheddar cheese and stir well.
Spread in the bottom of a lightly greased 9 x 13 baking pan. Bake for 35 minutes at 350ºF
Add remaining cup of cheddar cheese and sliced smoked sausage. Bake for an additional 15 to 20 minutes until the casserole is heated through and all of the cheese is melted well.
