At the center of the dinner table sits a smoked prime rib. You selected the meat and likely paid nearly the equivalent of a week’s worth of the federal minimum wage to buy it. You carefully chose the rub, watched it with slavish attention on the smoker for hours, rested it appropriately, and now you cut the first slice hoping that it won’t be disappointing. As a pitmaster or bbq cook, this is maximum pressure. With family and friends gathered around, you will be devastated if your effort has been in vain. This meal, usually a holiday, is an opportunity to show off your skills or risk embarrassment in front of those closest to you. There are a few simple steps to ensure you get a perfectly cooked prime rib every time, and we want to show you how to approach your next prime rib cook with complete confidence.

Temperature Measurement

The first element to make sure you get the perfect medium rare doneness (or whatever doneness you prefer) is temperature measurement equipment. While you could do this cook with Thermapen® NANO, we recommend using something that continually tracks temperatures so that you don’t wait too long to check temperatures. The RFX WIRELESS meat probe is a perfect choice that allows you to remotely monitor temperatures on your phone, but SIGNALS BBQ ALARM THERMOMETER is another great phone-free way to get accurate temperatures throughout the cook. Make sure to place your probe in the center of the meat. It is typically easiest to insert from one end of the rib roast, ensuring the probe stays centered so you will get accurate readings throughout the cooking process.

Next, you must choose the meat. Prime Rib is expensive. Unfortunately we don’t live in a world where it is the same price as bone-in, skin-on chicken thighs, but this is all the more reason to make sure to nail the cook. While there are USDA Select rib roasts available for purchase, we recommend USDA choice or higher if it fits your budget. The additional marbling pays dividends with a juicer final product. Look for a rib roast that is as even from one end to the other as possible. This will help you achieve even cooking. A noticeable fat cap is a good thing, but an extremely thick fat cap means you may be trimming off fat for which you paid a premium. 

The Rub

Now, let’s discuss the rub. Myriad barbecue rubs exist, so there is no shortage of options. You could choose something as simple as a heavy coat of kosher salt and some rosemary sprigs tied to the meat with butcher’s twine. Salt, pepper, and garlic is another simple but justifiably popular option. If your smoker doesn’t produce as much smoke flavor as you would prefer or you just want a greater diversity of flavors in your prime rib rub, let me give you a couple considerations to keep in mind. Lawry’s seasoned salt has been a go-to for a long time and with good reason. Anyone who has visited Lawry’s The Prime Rib restaurant knows this flavor. It combines salt with additional spices to provide a nice color and Umami kick to your prime rib. Many commercially available steak seasonings also work well. Let me caution you to avoid any rubs that are laden with sugar. Table sugar begins to burn around 375°F. For the final portion of the cook, we recommend a temperature of 500°F+, so there is a non-triviable possibility that a rub with sugar could burn and leave an unpleasant bitter taste on the outside surface of the meat. 

Regardless of the rub you choose, make sure that you taste it to gauge the amount of salt it contains. We recommend 3-4.5g of salt per pound of meat. Keep in mind that if you have a standing rib roast with bones attached, they add more weight, but don’t absorb salt. In that case, you can choose something closer to 3 grams of salt per pound. If you want to season with salt only, this is a simple matter of weighing the salt on a scale like the GRAVITAS PRECISION KITCHEN SCALE. If you want to do some calculations, you could find how many tsp of your particular rub would provide the requisite amount of salt. For instance, if you have a 5 lb prime rib, about 5.5 tsp of Lawry’s or 33 grams of this seasoning would give you just over 21 grams of salt. This fits in our recommended range for salt for this roast. At 3g/lb we would want 15g of salt, while at the upper limit of 4.5g/lb we would want to add 22.5g of salt. If you don’t want to bother with calculations, an easy way to get the saltiness right is to make up a rub of your choosing but withhold the salt. Weigh the salt and salt before adding other seasonings. Make sure that you add the salt to your rib roast 2-4 days before you plan to cook it, or at least the night before the cook. Salting beforehand and letting the roast sit on a wire rack in the fridge allows time for the salt to penetrate the meat so you can avoid an overly salty exterior with a bland interior. 

The Cook

Once you have your prime rib selected and seasoned, you can begin the cooking process. If you wish, you can tie your prime rib with butcher’s twine to get as round a shape as possible to prevent uneven cooking. If you cook gently enough in the smoker, however, you should be able to get near wall-to-wall pink without tying the prime rib. The best temperature to start your prime rib cook is usually around 225°F. This allows plenty of time to infuse smoke flavor and gently brings the internal temperature of the meat up without overcooking the edges. Depending on the thickness of the meat, this process could take anywhere from 2-4 hours, so it is vital that you monitor the temperature. Once the internal temperature reaches 120°, pull the prime rib out of the smoker and put it on a wire rack. This allows the meat to continue to carry over (usually to around 127°-130°), and gives you time to bring your smoker up as hot as it can go for the final stage of the cook. For the last step, get your smoker to 500°+. I usually cook in an offset smoker with the stack wide open. The temperature routinely reaches 600°. The high temperature is crucial, so that you can rapidly apply a sear without developing a gray band of meat around the outside. Lower temps can achieve a sear, but the time required to do so means the heat transfers to deeper layers, eliminating the possibility of wall-to-wall pink color.  Place the prime rib in the smoker for 60-90 seconds at max temp, max airflow. With heat resistant gloves, rotate the roast so that the opposite side of the smoker faces the direction of the heat for an additional 60-90 seconds. Once you’ve formed the crust, pull the prime rib from the smoker, allow to rest on a wire rack for at least 15 minutes, then serve.