1/2 cup melted butter
1 cup cheddar cheese
1 cup Velveeta
1/2 cup chopped red onions
1 can cream of chicken soup
1 cup sour cream
1/2 teaspoon dry mustard
salt and pepper
3 pounds frozen hash browns

Mix everything together in saucepan, except potatoes, and then heat the mixture on low. Stir mixture into the hash browns. Put into 9 X 13 baking dish which has been sprayed with Pam. Top with crushed corn flakes. Bake at 350 degrees for one hour.