Pre-heat oven to 500 degrees
Have Prime Rib at room temperature
Rub with flour, salt and pepper
4-5 lb roast: cook 25-30 minutes
5-9 lb roast: cook 35 minutes
After the above time, turn the oven off.
Leave roast at least 2 hours, but no more than 4 hours. Don’t open oven!!!!!
Should always be medium rare.