Preheat the oven to 450 degrees F. Place the prime rib bone-side down in a roasting pan. Combine the mustard, shallot and garlic in a bowl. Brush the mixture on the top and sides of the roast. Sprinkle mustard-coated tops and sides with Herbes de Provence, pepper and salt. Roast 20 minutes, and then reduce oven temperature to 325 degrees F. Finish cooking roast to desired doneness, allowing 20 minutes per pound - total cooking time - for rare, 25 for medium rare, and 30 for well done. When beef is ready, transfer to a plate, loosely cover, and rest 10-15 minutes before thinly slicing. To make jus to serve with the roast, remove fat from pan, pour in 3 cups of beef stock, and simmer 5-10 minutes.
Note: Herbes de Provence, a French-Style herb blend, is sold alongside the other bottled herbs sold at Thrifty Foods.