Prime rib is one of the tender cuts of beef it is and ideal for roasting and by this method.
Instructions
Preheat oven to 500° F (250° C).
When the oven is ready, season the prime rib with salt and pepper, and coat lightly with flour.
Place roast in the middle of the oven on a rack, bone down.
Roast 45 minutes.
Turn the oven off and keep the door closed at least 2 hours - and you can keep it up to five hours.
The meat will be perfectly medium rare.
Cut and serve.
Notes
Each rib on the bone will weight 2-3 pounds,
Roast 15 minutes per rib - i.e. 2 ribs = 30 minutes, 3 ribs = 45 minutes.
The meat can stand 2 to 5 hours waiting in the oven with no danger of overcooking. It will be perfectly medium-rare when it comes out.
Variantions
You can brush the surface with mustard, herbs and spices or a rub for meat..
Source
Food in U.S.A.