While the meatloaf is cooking, make the mashed potatoes. Place potato in a saucepan; cover with water. Bring to a boil; cover, reduce heat, and simmer 10 minutes or until tender. Drain.
Put potatoes into a ricer for best results. Return potato to pan. Add milk and remaining ingredients; stir with a spoon to desired consistency. If they are not creamy enough for you, add up to 1/4 cup more milk (just remember that they need to be stiff enough to pipe on top).