Cook the peeled potatoes until cooked through. Drain the water and let the potatoes evaporate on the hot stove. Then turn the stove back to a low setting.
Add the butter and some milk and mash with a potato masher. Gradually add more milk and continue pounding until it is evenly mashed. Then stir in the cream cheese. Finally, season with salt, pepper and nutmeg and serve sprinkled with roasted onions.