Cut pointed end off of garlic, place on a piece of aluminum foil. Fold foil to form a sealed packet. Bake at 400 degrees for 1 hour and let cool for 10 minutes. Open packet, squeeze pulp from garlic and set aside. This is easy to do in a toaster oven if you have one.
Bring potatos to a boil with enough water to cover in a large dutch oven. Remove and drain. Return to pan and heat 3-5 minutes over low heat until potatoes are dry. Set aside.
Heat cream in a small saucepan over low heat for 4 minutes or until just warm. Remove from heat and stir in sour cream.
Press potatos through a ricer or mash using a potato masher. Do not use a mixer or you get something related to wallpaper paste.
Stir in garlic pulp, melted butter, salt and pepper until blended. Gradually stir in warm whipping cream mixture, stirring just until blended.