If using fresh potatoes, peel and place in saucepan. Cover with cold water; bring to boil. Boil until a fork inserted indicates they're tender; drain.
In large bowl, combine potatoes, Cold Pack cheese, sour cream, butter, and pepper. Beat until light and fluffy. Spoon into buttered 2-quart casserole. Cover and refrigerate until ready to cook.
Preheat oven to 350°F. Bake 1 hour. Sprinkle top with bacon bits, paprika, and parsley, if desired.
Note: You may substitute 5 cups prepared instant mashed potatoes.