Trim the garlic head about 1/4 inch. Drizzle the olive oil over the head of garlic and wrap in foil.
Bake in a 350 F oven for 45 minutes. Or, place the garlic on a microwave-safe plate, cover, and microwave for 2 to 3 minutes, or until the cloves of garlic are soft enough to be squeezed out.
Mash the cloves thoroughly and set aside.
Peel and quarter the potatoes, and place them in a saucepan of boiling, salted water. Boil for 15 to 25 minutes until they are easily pierced with a knife.
Drain the potatoes, return them to the saucepan, add the butter and 1/3 cup of the milk. Mash until the potatoes are of a smooth consistency, adding more milk if necessary. (The amount of milk may vary, depending on the age of the potatoes.)
Stir in the remaining ingredients. Place the potatoes in a warm serving dish, and dot with more butter and a sprinkle of red chile powder, if desired.