Whether you're looking to wow your mother-in-law or show off your cooking skills to your friends and family, prime rib is an impressive choice for a special dinner. For the best results, choose a USDA Prime grade of beef, which is the highest grade of meat you can buy.
Place frozen prime rib in a pan and put it in the refrigerator for at least one full day to thaw before cooking.
Two to four hours before cooking, bring the prime rib out on the kitchen counter, covered, to reach room temperature. The exact time it takes depends on the size, so use your best judgment.
Preheat the oven to 450 degrees Fahrenheit.
Trim any excess fat off the prime rib, but leave a thin layer of fat, about 1 inch thick, to impart flavor on the beef.
Secure the rib bones to the bulk of the meat with cooking twine. Tie strips of cooking twine around the meat and in between the bones of the rib part so that the meat is held together with several pieces of string. This prevents the meat from falling off of the bone as it cooks, and also helps to keep it moist.
Smear butter on the cut ends of the prime rib. Season the rib with fresh ground black pepper and, if desired, kosher salt. (Some believe salting the meat before cooking dries it out. You have the option to salt before, or wait until after the prime rib is cooked.)
Place the ribs, rib side down, in a stainless-steel roasting pan at least 3 inches deep. Stick a meat thermometer in the thickest part of the meat.
Place the ribs in the oven for 15 minutes to sear it and crisp the skin.
Reduce the heat to 325 degrees Fahrenheit to finish cooking. Baste the roast with its own juices every 30 minutes.
Cook to your desired doneness. Beef is rare at about 120 degrees Fahrenheit, medium-rare at about 125 to 130 degrees Fahrenheit and medium-well at about 140 to 145 degrees Fahrenheit.
To prevent overcooking, remove the roast when it's about 10 degrees from the desired temperature. Cover with aluminum foil and let sit for 10 to 20 minutes. The temperature will continue to rise another 10 degrees, and the juices will redistribute throughout the meat, making it juicy.
Carve the prime rib into individual pieces and serve immediately.