Wash potatoes well with skins on. Prick potatoes and microwave until soft, about 7 minutes. (Or use your baked potato button if you have one). In large skillet, melt butter and saute onions over medium heat. Cube potatoes and stir into pan to coat in butter. Sprinkle with salt and pepper. Keep pan around medium heat and cook until potatoes are brown and crispy. (I find that if you leave them alone in the pan for 5 minutes at a time, then they brown quicker!). Serve warm.