1 (32 oz.) plain hash browns
1 stick butter, melted
1 med. onion, chopped fine
1 can cream of chicken soup, undiluted
1 (16 oz.) sour cream
1 (16 oz.) grated Mozzarella cheese

Melt 1 stick butter in glass 13x9 dish in microwave or oven. Add rest of ingredients and mix well. Bake at 350 degrees for one hour.