You'll never believe it. This can be started in mid afternoon but don't ask why it works! Any size rib of roast of beef, salt and pepper, no flour! Place beef in preheated 375 degree oven for 1 hour. Turn oven off. DO NOT OPEN OVEN DOOR. Rare 300 degree oven for 45 minutes before serving time, medium roast 50 minutes and medium well roast 55 minutes.