The original recipe came from this site http://whatscookingamerica.net/Vegetables/PotatoesMakeAheadMashed.htm
Make-Ahead Mashed Potatoes
5 pounds potatoes
8 ounces cream cheese, room temperature
1 cup sour cream
2 teaspoons onion powder
Salt and freshly ground black pepper to taste
2 egg whites, slightly beaten
4 tablespoons butter
1/3 cup chopped chives (optional)
Clean and quarter potatoes and cook in boiling water until tender when pierced with a fork
Drain and when cool enough to handle, peel.
I prefer peeling after cooking, much easier.
Rice or mash potatoes
Add cream cheese, sour cream, onion powder, salt, pepper, egg whites, and chopped chives (if desired); blend well. Dot with butter.
Cool mashed potatoes slightly, cover, and then refrigerate.
Note: The prepared mashed potatoes may be made up to a week ahead of time. If preparing ahead, place in an ovenproof baking dish, allow to cool slightly, cover, and refrigerate.
Preheat oven to 350 degrees F.
Take potatoes out of the refrigerator 30 minutes before baking.
Bake, loosely covered, 40 minutes or until steaming hot in center.
Take the prepared mashed potatoes out of refrigerator about 3-1/2 hours before serving time. Place in crock-pot. Cover and cook on low heat for approximately 3 hours, stirring once or twice.
After potatoes are cooked, stir, and then add some additional dollops of butter just before serving.
Makes 12 to 25 servings