Prime Rib You Won’t Believe
Any Size-
Place roast in a pan, and place in to a preheated 375 degree
oven for one hour.  DO NOT open the oven door!  
Turn the oven off.  Leave the oven this way for up to two hours.  
Now turn the oven back on to 300 degrees.  Cook until Roast
has reached desired doneness.  

Rare: 45 minutes
Medium rare: 50 minutes
Medium: 55 minutes

Allow ten minutes standing time on the counter to set up.
Remember, DO NOT open the oven door!