1/2 to 1 c. sour cream
1/2 to 1 c. cheddar cheese

Fix desired amount of mashed potatoes; can use instant potatoes. Place in pan so potatoes are 1-2 inches deep. Spread thin layer of sour cream on top of potatoes. Spread thin layer shredded cheddar cheese on top of sour cream. Place in microwave or oven until cheese has melted.