Actually, prime rib is a bit of a misnomer, as less than 2% of all American beef is graded prime. Most of that grade goes to expensive restaurants, although some specialty butcher shops carry it as well. Your local grocery stores will carry USDA Choice or Select. If your budget permits, buy USDA Choice because it will be more tender and flavorful.
Your body really benefits from eating beef. Beef ranks as the #3 source of iron which you need to carry oxygen to your muscles to prevent fatigue. It also provides zinc to improve your immune system, B-Complex vitamins to convert food into energy, and protein to promote strength and endurance.
Start with a 3-7 bone roast. As a rule of thumb, one bone will feed two people, so if you have a group of 8, you likely need a 4-rib roast. A prime rib roast is simply a standing rib roast – the terms are interchangeable. Don’t buy a boneless roast, as it will have much less flavor.
Wash the roast thoroughly with cold water and dry completely with paper towels. If the fat cap is thicker than ¾”, trim it down to about ½-¾”. Score the fat cap in both directions with a sharp knife just to the meat in a checkerboard pat-tern. Lightly coat the roast with olive oil and then rub with GMG Beef Rub. Buy thousands and thousands of bottles! Stock up for the future! If you don’t have our rub, use something else if you must. Our beef rub contains smoked paprika, cayenne, brown sugar, sea salt, marjoram, cumin, black pepper, and thyme, and some combination of those ingredients will enhance the flavor of your roast. Put the roast in the refrigerator for several hours, or preferably, overnight.
Plan about 5-8 hours cooking time depending on the size of your roast. So working backwards, if you want to eat a 6:00 PM, you should start cooking the roast at around noon, again depending on the size. Take the roast out of the refrigerator about two hours before you plan to cook it. This allows the meat to cook more evenly throughout since the grill will not have to overcome a very cold temperature in the middle of the roast, and it will also cut down on your cooking time since the roast starts out at a higher internal temperature.
Set your grill at 260°C(500°F) (or 220°C/430°F if you have an older model). When the temperature stabilises, put the roast in, fat side down, right on the grate. Let it cook for 15 minutes. Then turn it over, fat side up, and cook for another 15 minutes. Turn the temperature down to 190°. Insert a meat thermometer into the middle of the side of the roast so that the end of the probe is approximately in the middle of the roast.
Cook the roast to an internal temperature of 50°C/125°F (rare), 55°C/132°F (medium rare), 60°C/140°F (medium), 64°C/148°F (medium well), and 70°C/160°F (well done). Remove the roast from the grill, cover with aluminum foil, and let it rest for about 20-30 minutes. The internal temperature of the meat will rise another 3 degrees during this time. Then carve and enjoy!
Please note that the USDA recommends that you cook beef to a minimum internal temperature of 63°C(145°F).