1 lb. frozen hash browns
1/2 med. chopped onion
1/2 stick butter
3 oz. grated Cheddar cheese
1 can mushroom soup
1 c. sour cream

Thaw potatoes. Saute onions. Mix sour cream, soup, cheese, salt, and pepper; add to first mixture. Sprinkle corn flake crumbs on top. Drizzle 2 tablespoons butter over. Bake in flat casserole at 350 degrees for 40 minutes.