Saute one medium onion, chopped, in 3 Tbsp. oil or butter.
When soft, add 6 cups chicken stock or chicken broth, 5 cups baked potatoes, cubed and peeled.
Bring to a simmer, and add 1 cup heavy whipping cream, 1 cup sour cream, and salt and pepper to taste.
Bring to a simmer again, and serve with baked potato toppings, such as bacon, chopped chives, or cheese.
Source: Joy of Cooking