Prep Time: 20 minutes
Cook Time: 195 minutes
Total Time: 215 minutes
Servings: 14
Combine pepper, salt, garlic, cornstarch and dried herbs. Tie the prime rib roast every 1 1/2 to 2 inches with butcher’s twine. Rub the entire roast with seasoning blend and refrigerate overnight, wrapped tightly in plastic wrap on a sheet pan.
Preheat oven to 275°F. Place roast on a rack lined with foil in a shallow roasting pan, fat-side down. Roast, uncovered, for 120 minutes.
Flip roast so that fat side is now up; discard foil. Insert an ovenproof meat thermometer into thickest part of the roast, avoiding bone or fat. Continue roasting approximately 1 hour. Look for 120-125°F on thermometer.
Rotate roasting pan and increase oven temperature to 450°F. Roast on high for 15 minutes to deepen crust. Final internal temperature should be 130-135°F when pulling from oven for a deep pink interior.
Transfer roast to a cutting board and let rest 20 minutes before removing twine and carving.