Place the prime rib on a roasting pan fat side up. (I use
this roaster, and highly recommend it.) Roast the meat in the oven until the center of the roast reads 120°F (50°C) on a meat thermometer for medium-rare, or 130°F (55°C) for medium doneness, about 3.5-4 hours. (This
Thermapen Mk4 meat thermometer is my favorite! Super quick and reliable! <-
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