2 lbs. bag Tater tots
1/2 c. grated onion, or to taste
1/4 c. melted butter
8 oz. carton sour cream
2 cans mushroom soup
1 c. grated cheddar cheese

OPTIONAL TOPPING:

1 c. crumbled cornflakes mixed with 1/2 c. melted butter

Blend sour cream, mushroom soup and cheese. Spread over potatoes. Cover with foil and cook 45 to 60 minutes at 350 degree oven. Add topping during last 15 minutes.