Guest Post: How to Cook Prime Rib

Today's post is a guest post by my husband, Paul. If you're following us on Instagram, you might know him by his Insta page, ChicagoBeerBros. 

Anyway, from time to time he makes prime rib for the family and once we got an iGrill digital thermometer by Weber, it was a big game changer. He was able to place a probe in the meat as it cooked, but the digital reader is outside the oven or grill and then syncs to his mobile device, so that he can monitor the temperature. So, in the summer, he was able to put a prime rib roast or other meat on the grill and monitor the temp from in the cool air-conditioned house. Today he made it in the oven but could keep an eye on it from his desk in the basement. As he was preparing to cook today, I told him he needed to write down his instructions so that next time we could remember at exactly what temperature to remove it from the oven. He did even better than that. He wrote a full post:

How to cook Prime Rib

Start by choosing the size of your Prime Rib. I have a family of carnivores and for them I plan on 12 to 16 ounces per individual (keep in mind some of that will be fat and bone). If you are making several side dishes to go with it and have lighter eaters, then 6 to 10 ounces per individual should be a good portion. You have 2 choices, bone in or no bone. I like the bone in, tied with string by the butcher, because the bones serve as a roasting rack to support the roast while cooking. I trim the extra meat from the bones and mix it with dog food for our two dogs. 

As far as seasoning goes, we all have personal preferences. I use a steak seasoning from the local butcher shop, Howard & Sons. Sprinkle or rub the seasoning all over the meat. I tend to put the seasoning on a little heavy. The meat seems to tolerate a fair amount without overwhelming the palate. I also like to apply the seasoning the night before. Although it’s not necessary, I feel that the flavors have more time to break down into the meat. Remove the prime rib from the refrigerator about an hour before placing it in the oven. This allows the temperature of the meat to rise a little, which helps it to cook more evenly. 

Preheat your oven to 450. Place your roast in an aluminum pan slightly larger than the roast. The pan will collect the juices and keep the meat moist. Do not cover the roast. Let it bake for 25-30 minutes to sear the outside. This will prevent the meat from drying out while cooking and makes for a delicious appearance. Then reduce the heat to 350. I like to cover my prime rib with aluminum foil after searing the outside, although this is not necessary. I cover the roast to keep it moist, but you can simply continue cooking without covering if you prefer. At a cooking temperature of 350 the meat will take approximately 17 minutes per pound to cook. If you want a slightly juicier and more tender cut then cook at 325 and add a little to your total cooking time. 

Now, this is the important part. You will want to use a digital thermometer to monitor the internal temperature of your roast. It is the temperature that will determine rare, medium rare or well done! Place the thermometer in the center of the roast. I like to place the temperature probe at the top but you can also place it in the side if you choose. Just make sure it is in the center of the roast otherwise you will not get an accurate internal temperature which will cause an under or overcooked roast. Also, use a thermometer that has a probe tethered to a readout that is outside the oven. If you use a thermometer that must be read by opening the oven door, you will not be able to maintain the temperature of the oven. Lookin’ is not cookin’ as I was taught. 

If you want rare then you’ll want an internal temperature of 120-125 degrees; medium rare 130-135; medium well 140-145; and well done 150-155. 

Another important note to make sure you achieve your desired internal temperature is that the roast will continue to cook after removal from the oven. For example, I like my roast to be a medium rare (internal temperature of 130-135). So I remove the roast from the oven when the internal temperature reaches 120-125 because I expect a 7 to 8 pound roast to rise 10 to 12 degrees after removal from the oven. Keep in mind that the larger the roast, the more the temperature will rise after removal from the oven. The opposite is also true, the smaller the roast, the less the temperature will rise after removal from the oven. When the temperature no longer rises, I ring the dinner bell. 

Removing the roast from the oven also allows the meat to rest. During cooking, the natural juices move to the outside of the meat. Allowing the meat to rest after removal from the oven gives time for the juices to flow back to the center of the roast. The juices will make the cut more visually appealing as well as more flavorful, which your hungry family will appreciate. 

Tonight’s roast was 7 pounds 4 ounces. I removed it from the oven at 125 degrees still covered with aluminum foil. While resting on the counter, the temperature continued to rise to 137 degrees. Once the temperature stopped rising I removed the foil and cut the roast into ½ inch slices. The ends were medium to well done. The remaining was medium rare. 

My wife made sides of asparagus, corn, mashed potatoes, biscuits, spinach salad, broccoli, butter beans and horseradish sauce for the prime rib. 

I know it was a good meal because everyone was busy eating without talking. With our large family the table is rarely that quiet.