1 (32 oz.) pkg. hash browns
1 lb. sharp cheddar cheese, shredded
1 can cream of chicken soup
1/2 lb. sour cream
Onion, chopped; optional

Thaw hash browns. Mix all ingredients in a large bowl. Put into a 13 x 9 baking dish. Bake at 350 degrees for 1 to 1 1/2 hours or until lightly brown on top.