8 lg. potatoes
2 tbsp. onion salt
1 pt. sour cream
4 tbsp. butter
1 c. grated cheddar cheese

Peel and cook potatoes until soft. Mash potatoes with onion salt and sour cream. Add butter; mix well. Place in 2-quart casserole dish and top with cheddar cheese. Refrigerate overnight. Bake at 350 degrees for 1 hour, uncovered.