Beautifully marbled with fat, this roast is rich, juicy, and tender—a feast for the eyes and the belly.

How to Cook Prime Rib

It’s also very easy to cook. You just start it in the oven at a high temperature to get good browning on the outside of the roast. Then, cook it at a lower temperature to make sure the meat in the center doesn’t get overcooked.

Why Prime Rib is Classic for Occasions

There’s usually something for everyone with this roast. The ends are well done for those who can’t tolerate pink. The center should be a vibrant pink for those of us who must have our beef on the rare side.

How Many People Does Prime Rib Roast Serve?

A full rack of prime beef is 7 ribs, which will easily serve 14 to 16 people (or more!). A full rack will not fit in my oven, so when I’m feeding a crowd, I cut the roast in half (3 ribs on one roast and 4 ribs on the other) and cook them in separate ovens. As for estimating how big a roast you’ll need, the butchers I’ve talked to say to estimate 2 people for every rib. In my experience, that’s a LOT of meat! For the roasts we get, and given that we are serving a lot of food in addition to the roast, 3 people per rib is fine. If you want to err on the generous side with plenty of leftovers, aim for 2 people per rib.

What Grade of Meat is Prime Rib?

Note that just because you are ordering a “prime” rib, it doesn’t mean that you are getting USDA Prime. Because of high cost and fewer sources over the past decade or two, USDA Prime Grade prime rib has been replaced by most markets with USDA Choice Grade prime rib roast. Most “prime ribs” we get from the market are actually USDA Choice quality. If you want USDA Prime prime rib, which has more fat marbling throughout the meat, and which can easily cost 50 percent more per pound, you will likely need to special order it from your butcher. Prime rib is best served rare or medium rare. Once it’s overcooked, you can’t un-cook it, though you can wait for it to cook a little longer.

For a rare roast: 115°F.For medium rare: 120°F.For a medium: 130°F.

Let it sit for 15 to 20 minutes before serving. As the prime rib roast rests, the internal temperature will rise 5 to 10 degrees.

Favorite Sides for a Prime Rib Roast

Horseradish Sauce Yorkshire Pudding Creamed Spinach Perfect Mashed Potatoes Roasted Brussels Sprouts

The most important piece of advice I can give you regarding cooking a prime rib roast is to use a good meat thermometer! With a remote thermometer, you can tell exactly what the temperature of the meat is without having to open the oven door. I recommend this ChefAlarm by ThermoWorks.

1 (10-pound) standing rib roast, 3 to 7 ribs (estimate serving 2-3 people per rib), bones cut away from the roast and tied back to the roast with kitchen string (ask your butcher to prepare the roast this way)

Salt

Freshly ground black pepper

For the gravy

1/4 cup fat and drippings from the pan

1/4 cup all-purpose flour

3 to 4 cups water, milk, stock, or beer

Salt, to taste

Freshly ground black pepper, to taste

There are so many variables involved that affect cooking time, this is why you should use a meat thermometer. A prime rib roast is too expensive to “wing it”. Err on the rare side, you can always put the roast back in the oven to cook it a bit longer, if it’s too rare for your tastes. To estimate the total cooking time, allow about 11 to 12 minutes per pound for rare and 13 to 15 minutes per pound for medium rare. The actual cooking time will depend on the shape of the roast, how chilled your roast still is when it goes into the oven, and your particular oven. A flatter roast will cook more quickly than a thicker one. A chilled roast will take more time than one closer to room temp. Check the temperature of the roast using a meat thermometer an hour before you expect the roast to be done. For example, with a 10 pound roast, you would expect 2 hours of total cooking time for rare (15 minutes at 500° and 1 3/4 hours at 325°). In this case, check after 1 hour 15 minutes of total cooking time, or 1 hour after you lowered the oven temp to 325°. (A benefit of using a remote thermometer is that you don’t have to keep checking the roast, you’ll be able to see exactly what the temperature is by looking at the thermometer outside of the oven.) Then, using a sharp carving knife, slice meat across the grain for serving, making the slices about 1/2-inch to 3/4-inch thick. Place the roasting pan on the stovetop on medium high heat. Use a metal spatula to scrape up drippings that might be sticking to the pan. When the fat is bubbly, sprinkle 1/4 cup of flour over the fat and drippings in the pan. Stir with a wire whisk to incorporate the flour into the fat. Let the flour brown (more flavor that way and you don’t have the taste of raw flour in your gravy.) Slowly add 3 to 4 cups of water, milk, stock, or beer to the gravy. Continue to cook slowly and whisk constantly, breaking up any flour lumps. The gravy will simmer and thicken, resulting in about 2 cups of gravy. Season the gravy with salt and pepper and herbs to taste.