How to Expertly Cook a Prime Rib Roast to Your Ideal Doneness
Prime rib is ideal for entertaining because it requires little hands-on time and serves many (depending on the size of your roast). Even the leftovers from a slow roasted prime rib are fabulous. Learn how to buy, prep, and roast this top cut of beef so you'll be equipped with everything there is to know about how to cook prime rib roasts.
Prime rib is another name for a beef rib roast or standing rib roast, which has the rib bones intact and is considered to be one of the best-quality beef cuts for roasting. The rib bones add flavor and act as a natural rack for the meat to roast on. To make carving easier, you can ask your butcher to cut the rack from the roast. Save the rack and use kitchen string to tie the roast back to the ribs for roasting. Then, just cut the strings and remove the bones before slicing. To cook your most perfect prime rib roast follow our tips that walk you through from purchasing to carving.
Step 1: Buying Your Prime Rib Roast
When purchasing your prime rib roast, figure about 2 to 3 servings per 1 pound meat (about two servings per rib). Rib roasts vary in size from 4 to 10 pounds. If possible, order your roast ahead, especially during the holidays, when prime rib roasts are especially popular. Remember to ask for the rack (or chine bone) removed for easier slicing, if you like. As with selecting all kinds of beef, look for beef that has a fresh pink/red color.
Test Kitchen Tip: The name "prime rib" is a little misleading because the beef may not be prime grade, which is the highest USDA beef grade with the most marbling. Choice, the most common grade found at market, has a little less marbling will still be juicy and flavorful.
Step 2: Preparing the Prime Rib
Preparing prime rib for cooking can be as simple as sprinkling it with salt and pepper or rubbing it with olive oil and a dry spice rub. Another easy way to add flavor is to stud the roast with garlic. Using the tip of a small knife ($10, Bed Bath & Beyond) poke several 1-inch-deep slits randomly over the roast. Cut 2 or 3 garlic cloves into 6 to 8 lengthwise slivers, and tuck the slivers into the slits.
Place the roast, fat side up, in a 15½ x 10½ x 2-inch roasting pan ($60, Williams Sonoma). Insert an oven-going thermometer ($7, Target) into the center of the roast, making sure it does not touch bone or the pan.
Test Kitchen Tip: If you don't have an oven-going thermometer, use an instant-read thermometer inserted into the thickest portion of the roast to test the temperature (do not keep this kind of thermometer in the roast during cooking). Keeping a close eye on internal temperature is how you know exactly how long to cook prime rib without overcooking it.
Step 3: Cooking Prime Rib
What's the best way to cook prime rib roast? It's right in the name—roast it! Cooking time will depend on the size of your roast and the prime rib temp you like best. Use these guidelines for how long to cook prime rib roast to your perfect doneness.
Roast the meat, uncovered at 350°F, until desired doneness.
- 4 to 6 pounds: roast 1¾ to 2¼ hours for medium rare (135°F) or 2¼ to 2¾ hours for medium (150°F)
- 6 to 8 pounds: roast 2¼ to 2½ hours for medium rare (135°F) or 2¾ to 3 hours for medium (150°F)
- 8 to 10 pounds*: roast 2½ to 3 hours for medium rare (135°F) or 3 to 3½ hours for medium (150°F)
*Test Kitchen Tip: Roasts weighing more than 8 pounds should be loosely covered with foil halfway through roasting
After removing the roast from the oven, transfer it to a cutting board ($30, Bed Bath & Beyond). Cover the meat with foil and let stand for 15 minutes. This allows the juices to redistribute, preventing them from draining out during carving. The meat temperature will rise about 10°F while it stands (the timings and temperatures listed above allow for this). This is key to a perfect prime rib roast, you don't want it to get overcooked and dry so take it out of the oven 10 degrees early.
Step 4: Carving Prime Rib Roast
On a cutting board, turn the roast on its side; remove a thin bottom slice if needed to stabilize the roast on a flat surface. Insert a large fork in the side of the roast, below the top rib. Carve across the front toward the rib bone. Cut along the rib bone with the tip of the knife to release the slice from the bone. Remove slice and transfer to a platter. Repeat with remaining slices.
Storage Tip: Refrigerate leftover meat up to 3 days. Use it to make warm or cold beef sandwiches on buns or dinner rolls spread with horseradish mayonnaise.
Prime Rib Au Jus
A prime rib au jus sauce is very standard to serve with your prime rib roast. For the best flavored au jus, use the drippings left in the roasting pan. Once your meat is removed from the roasting pan, spoon the drippings into a fat separator or glass measuring cup. Skim off the fat. Place your roasting pan over medium heat on the stove top (you may need to use a couple burners, depending on the size of your pan). Add the drippings, beef broth, and other desired seasonings to the pan. Heat until bubbly, scraping up any brown bits from the bottom of the pan. Thicken as desired. Strain before serving.
Try our basic beef au jus recipe, or the merlot prime rib au jus in this prime rib recipe. For a shortcut sauce, serve with purchased horseradish ($4, Target) sauce or another favorite topper. Or, you may find your perfectly cooked prime rib roast requires no sauce at all, just let the meat shine all on its own.