Bake or boil the potatoes until tender. Then cut in halves or quarters and scoop out to leave a shell ¼ inch to ½ inch thick. (Reserve the scooped-out portions for mashed potatoes or another use.)
Prepare the smoker for barbecuing, bringing the temperature to 200°F to 220°F.
Rub the potato skins with a thin coat of butter or oil. Sprinkle the skins, i