Hash Brown Potato Casserole
["1 (2 lb.) bag thawed hash brown potatoes", "1 tsp. salt", "1/2 c. chopped onion", "1 (10 oz.) can cream of chicken soup", "1 (10 oz.) can Cheddar cheese soup", "1 (8 oz.) carton sour cream", "2 c. crushed cornflakes*", "1/2 c. melted butter or margarine*"]
["*May substitute 2 cups shredded Cheddar cheese for this topping."]
["potatoes", "salt", "onion", "cream of chicken soup", "Cheddar cheese soup", "sour cream", "butter"]