preheat oven to 350
Using a 9x13 baking dish, grease bottom
spread frozen hashbrown chunks into bottom of 9x13 dish
melt butter in a fry pan and add onions. Saute
In separate bowl, mix sour cream, cream of mushroom soup, cheddar cheese
add sautéed onions to sour cream mix
spread mixture over frozen potatoes
top with generous amount of corn flakes or additional grated cheddar cheese
bake at 350 for 1 hour