Preheat oven to 350 degrees.
In a small bowl, combine all ingredients except roast.
Place prime rib in a roasting pan and rub it intensely with garlic Dijon mixture.
Roast for 1 to 1 1/2 hours or until a meat thermometer registers 145 to 160 degrees (depending on desired level of doneness).
Allow roast to sit for about 20 minutes before serving.