1) Saute onions in melted butter. Add soup and sour cream and stir.
2) Add grated cheese and stir constantly as it melts.
3) Add salt and pepper to taste.
4) Add frozen hash brown and stir until coated with sauce.
5) Pour into 13x9x2" pan. Top with crushed corn flakes
6) Bake at 375 degrees for 25-30 minutes until slightly brown and bubbling.