2 pounds hash browns, frozen, ore-ida
1/2 cup melted butter
1/2 cup chopped onion
1 teaspoon salt
1/4 teaspoon pepper
1 pint sour cream
1 can cream of chicken soup
2 cups grated cheddar cheese
2 to 3 tablespoons horseradish
Defrost potatoes.
Mix all ingredients in large bowl, saving enough cheese to sprinkle over top of casserole.
Pour into greased large casserole; top with remaining cheese.
Bake at 350 degrees for 45 minutes.