Cut off pointed ends of garlic bulbs; place garlic on a piece of aluminum foil, and drizzle with oil. Fold foil to seal.
Bake at 350° for 1 hour; cool to touch. Squeeze pulp from garlic cloves; set aside.
Bring potato, 1 teaspoon salt, and water to cover to a boil in a Dutch oven; boil 20 to 25 minutes or until tender. Drain.
Mash potatoes, or press through a ricer; stir in garlic, remaining 1 teaspoon salt, whipping cream, and next 4 ingredients until smooth.