Melt 1 stick of butter in a throw away pan. Scrub potatoes and dice them into the pan, skins and all, salt and pepper. Cover the pan with aluminum foil and place on grill. The potatoes will fry on the bottom and bake on the top. When the potatoes are done (approximately 45 minutes to an hour) lift off foil, cover potatoes with Velveeta cheese. Cover and return to grill until cheese has melted and run down through the potatoes.