Au Gratin Potatoes

By Sonya A.

2 lb. package of frozen hash browns
1/2 c. chopped onion
1/2 c. margarine or butter
16 oz. sour cream1 can cream of mushroom soup
2-3 cups shredded cheddar cheese

Thaw frozen hash browns in bag in microwave for 3 minutes. Put chopped onion and butter or margarine in a large microwave safe bowl and microwave for 2 minutes to begin cooking onion. Mix all ingredients together in large bowl, reserving about 1 cup of the cheese to put on top. Transfer to 9X13 pan. Sprinkle with reserved cheese and bake, uncovered, at 350' for 1 hour.