Cut potatoes into small, bite-sized cubes. Rinse potato cubes with cold water, and drain well. Melt butter or margarine in a large skillet over medium heat. Place potatoes in the skillet, and stir to coat with butter. Season with salt and pepper (make sure not to over season). Cover with a lid, and cook for 10 minutes. Remove the lid, and cook for another 10 minutes, turning frequently until brown and crisp on all sides.

*For lactose intolerant people, cook two potatoes in vegetable oil instead.