Steam the potatoes in ½ inch water, covered, until very tender, 15 to 20 minutes. Drain.
Lightly mash the potatoes, milk, butter, 1½ teaspoons salt, and ½ teaspoon pepper in a large bowl.
Serve warm topped with additional butter and pepper, if desired.
Smashed or lightly mashed makes lumpy potatoes. Just use your mixer and let it beat the potatoes while you do something else.
