Thoroughly rub the roast with the salt and lots of black pepper just prior to going in the oven*
Roast in the oven (bone side down) for 15 minutes.
Reduce the oven temperature to 275 degrees F and continue roasting until the desired internal temperature of the meat is reached.
Remove from the oven and let rest for at least 20 to 40 minutes (depending on the size of the roast) to help ensure juices stay in the roast.
Remove the bones and carve as desired. Serve with the optional “Au Jus” as described above.
*Chef Dez note – only salt the roast just prior to putting in the oven. If salt is left on meat for extended periods of time, juices are drawn to the surface of the meat and will inhibit a good searing of the outer crust.
There are a number of tips to cooking a prime rib roast to perfection. The most important is to use a meat thermometer. You can choose from an oven-proof one that is inserted at the beginning of the cooking time and left in, or an instant read one that is used to check the internal temperature at chosen intervals (but not left in the oven). Although both work very well to keep your roast from over cooking, I recommend the oven proof one because you simply leave it in the roast. The result is less punctures to the meat and thus more juice retention.
Rare: 120 to 125 degrees F
Medium Rare: 130 to 135 degrees F
Medium: 140 to 145 degrees F
Medium Well: 150 to 155 degrees F
Well Done: 160 degrees F and above
I have also provided an approximate cooking time chart, but I stress that this is just an informal guideline and not to be used in replace of a meat thermometer. There are many variables that a time chart just cannot encompass: temperature of the meat prior to cooking, exact size/shape of the roast, oven temperature accuracy, etc.
Also, the closer you can bring your roast to room temperature before cooking (without jeopardizing food safety and leaving it out too long) will result in a more uniform doneness. If you put a cold roast in the oven the outer parts of the inside flesh will be overdone in comparison to the center of the meat (where you thermometer is inserted). This time chart is loosely based on this procedure with the result of a 130 degree F medium rare result:
Approx. Weight Oven Temp Est. Time
4 – 5 pounds 450/275 deg F 1.25 to 1.5 hours
7 – 8.5 pounds 450/275 deg F 1.75 to 2.5 hours
9 – 10.5 pounds 450/275 deg F 2.5 to 3 hours
11 – 13.5 pounds 450/275 deg F 3 to 3.5 hours
In order to create a flavourful crust, start with a cooking temperature of 450 degrees F for the first 15 minutes of the cooking time. Then reduce the oven temperature to 275 degrees F (without removing the roast from the oven) and continue cooking until your desired internal temperature has been reached. This lower temperature for the remaining majority of the cooking time will help to create a more even cooking of the meat.
Also, it is important to note that prime rib roasts should always be cooked with the bones intact to create more flavour in the meat. The bones also act as a natural rack for the meat to cook on when placed bone side down in your roasting pan. If desired, you can request that the bones be removed and then tied back on for easy removal before carving. By cooking with the bones on the bottom this leaves the fat cap on the top of the roast for maximum protection from drying out.
If a simple dipping “Au Jus” is desired for serving, remove the roast from the pan and remove almost all of the liquid fat, but leaving the beef drippings in the pan. Put the pan on the burners of your stove. Add 2 parts beef stock and 1 part red wine. Boil until reduced by half in volume. Season with salt & pepper to taste.