Deluxe Prime Rib For the beef to qualify it has to be free of bruises, evenly marbled steer meat, dry aged for at least 29 days and be no more than 13 pounds. A one inch thick fat cap is also required. Start by rubbing a spice mixture which contains equal amounts of kosher salt, garlic powder, beef base, ground black pepper, keens mustard powder and mild paprika. The spice rub is most important to making a tender roast. Massage this mixture all over the room temperature beef until it was well coated. Now place the roast onto a thick roasting pan and pour about a cup of...