Preheat oven to 350 degrees.
Mix soup, sour cream and cheese together.
Mix in hashbrowns (you will probably need to use your hands for this).
Bake for 1 hour.
Optional Corn Flake Topping
Melt butter in microwave.
Pour melted butter over Corn Flakes and stir. You may need to add more Corn Flakes to soak up more of the butter.
Spread over cheesy potatoes.
Bake 1 hour at 350 degrees.