Smoking prime rib follows the same principles as those for roasting a prime rib, with only a few modifications. Most of the same basic rules apply however: choosing a great cut from the start, checking for internal temperatures, and allowing for the resting period being the most important things to keep in mind no matter which actual cooking method is applied. Really the only change from there will be the cooking temperature – smoking involves keeping the heat low and slow, and that works beautifully with a prime rib.
Although it is possible to do some smoking on the stove top or in the oven, the longer cooking time that a prime rib needs means you really do need to take it outside. You can smoke with either an electric or gas smoker, or with a standard charcoal or gas grill. Which one doesn’t really matter at all – what does matter is keeping the heat inside low for a long period of time. This means about 225F ideally, but no lower than 200F, and no higher than 300F. The point here is to get a nice, long heat, allowing the wood chips to smoke away gently, imparting that lovely flavor to the already fabulous beef, enhancing it perfectly. Whichever method you choose, smoker, charcoal or gas, be prepared to monitor the temperature inside. The trickiest way is with charcoal – you’ll need to be able to add briquettes or lump charcoal, and it can be difficult to maintain even temperatures. But the argument can be made that this is also the way to develop the best flavor.
The second choice is for the type of smoke you want. Because prime rib is beautifully tender, there isn’t much in the way of connective tissues in it. While that makes the texture close to butter, it also means the flavor can be overwhelmed totally with heavy seasonings. The same way with smoke – the stronger smoke flavors can be too heavy for this particular cut. So stick with light smoke, and fruits woods if you can. Try oak, or apple. Both are wonderful, and usually readily available, if not in supermarkets, then in hardware stores with a little hunting.
Finally – pick your seasonings carefully. Remember you’re going into this in order to enhance the beef, not cover it up. So kosher salt and freshly cracked black pepper certainly, but keep the rest simple, if you choose to use anything additional at all. A little rosemary thrown in with the wood chips can be terrific, if added toward the end, or a paste of garlic (or roasted garlic) and olive oil. But the smoke will also add a flavor of its own, so the final product can quickly become busy instead of lovely and complex.
At this stage you’re ready to go! Soak your wood chips in a little water while the smoker preheats and the roast comes to room temperature. Season the roast how you choose. When the interior of the grill or smoker is at 225F, place a thermometer probe into the thickest part of the beef, away from the bone, and place the roast on the grates. Place an aluminum pan under the roast to catch the drippings – smoky au jus later is unbelievable. That’s it! All you want to do at this point is keep an eye on the temperatures – the one inside the grill, and the internal temperature of the roast itself.
Don’t worry about cooking times – there’s no way to accurately use a cooking time chart. There are too many variables. In general, at this temperature, you’ll need about 20 minutes per pound for rare, and up to thirty minutes per pound for well done – but that depends on the temperature of the roast, the temperature of the fire, how far away from the heat the grates are, the amount of air flow in the smoker or grill – all kinds of things. So while the cooking time guides might be all right for a general idea (if dinner is to be at 7:00, I need to start the roast at 4:00), that’s the only thing it should be used for. Otherwise, all of those variables mean you can over or under cook the roast within as little as ten minutes. A thermometer takes away all of the variables and puts control and exactitude in your hands. That alone puts you nearly at the finish line with perfect prime rib.
When the internal temperature reaches the degree of doneness you wish (125F, rare, 135F, medium, 145F, well done) pull the roast off the heat, and allow it to rest. Resting is critical – it allows for carryover cooking to finish the roast to perfect doneness, and allows the juices in the roast to redistribute throughout the meat, instead of staying at the surface. This means juicy beef – not a juicy platter and dry beef. Allow the roast to rest for no less than twenty minutes, and for a full sized standing rib roast it should be thirty minutes at minimum. Use this time to make au jus, gravy or Yorkshire pudding from that beautiful pan full of drippings.
That’s all there is to it – just keep in mind the basics. Choose a good cut, have a thermometer, keep the heat low, choose a mild smoke, and allow for resting. You’ll be ruling the prime rib world in no time.