Prime Rib Roast with Mustard Rub

¼ c Dijon mustard stir smear fridge 2+ hours unfridge 1–2 hours roast 10 minutes at 450°F roast 15–30 minutes per pound at 275°F stop roasting at 130–135°F rest 15–30 minutes
1 T dry mustard
1 T sugar
¼ t salt
pepper to taste
1 4-rib beef roast (7–9 pounds), trimmed  
  1. Stir together wet and dry mustards, sugar, salt, and pepper.
  2. Rub mustard marinade on outside of roast.
  3. Refrigerate at least 2 hours.
  4. Before roasting, rest at room temperature 1–2 hours.
  5. Roast 10 minutes at 450°F.
  6. Continue roasting at 275°F for 15–30 minutes per pound until internal temperature reaches 130–135°.
  7. Let stand 15–30 minutes before carving.

Shamelessly stolen from The Joy of Cooking.