In a large bowl mash Potato's until smooth. Cut cream cheese and butter into small chunks and beat into Potato's Stir in sour cream. In a small bowl mix remaining ingredients and stir into potato mixture. Whip until fluffy. Place in a casserole dish and refrigerate at least two hours or overnight.

When ready to cook preheat oven to 350. Bake 45 minutes or until a light brown crust forms on top.