
Prime rib, also known as a standing rib roast, is a cut of meat that makes an impressive centerpiece for <a href="https://cooking.nytimes.com/topics/holiday-recipes">a holiday meal</a> or special occasion. There are several different ways to cook a prime rib, but the most forgiving is the <a href="https://www.nytimes.com/2022/05/14/dining/how-to-grill-the-perfect-steak.html"><span>reverse sear</span></a>: The roast goes into the oven at a low temperature for several hours, then rests on the counter before getting a final blast of high heat. While it’s not difficult to cook, precision is important here, so you should use a meat thermometer inserted into the thickest part of the roast to test the temperature. This method works well with smaller or larger rib roasts, though the time will vary accordingly. Serve with jus and traditional side dishes, such as <a href="https://cooking.nytimes.com/recipes/1017129-yorkshire-pudding"><span>Yorkshire pudding</span></a><span>, </span><a href="https://cooking.nytimes.com/recipes/11356-french-green-beans-and-shallots"><span>green beans</span></a> and <a href="https://cooking.nytimes.com/recipes/1016898-mashed-potatoes"><span>mashed potatoes</span></a>.
The night before you plan to cook the prime rib, place the roast on a rimmed sheet pan or platter. Season all over with 2 tablespoons of salt and refrigerate, uncovered, overnight. Two hours before cooking, let the roast sit on the counter to come to room temperature.
Arrange an oven rack in the lower third of the oven and heat to 250 degrees.
Position the roast with the tips of the bones facing up. With a sharp carving or chef’s knife, create a flap by slicing between the meat and the bones, staying as close to the bones as possible and stopping just before they’re separated from the roast. Flip the roast so the bones are underneath and the meaty side is up. Use several pieces of kitchen twine to secure the bones back in place against the roast, tying between each set of ribs. (This will make it easier to remove the ribs when carving, after the meat has been roasted.) Alternatively, a butcher can do this for you.
In a small bowl, whisk together the olive oil, rosemary, garlic, 1 teaspoon salt and 1 teaspoon pepper. Rub all over the meat. Place the roast bone side down on a wire rack set over a rimmed baking sheet or on a rack in a large, shallow roasting pan. Roast for 3 1/2 to 4 hours, until an instant-read thermometer inserted into the thickest part of the meat registers 125 degrees for medium-rare. Remove the prime rib from the oven, tent it loosely with foil and allow it to rest for at least 20 minutes and up to 1 hour. (The temperature will rise 5 to 10 degrees as the roast rests.)
Meanwhile, increase the oven temperature to 500 degrees. When the oven comes to temperature, remove the foil and return the roast to the oven until the meat is nicely browned all over, 5 to 10 minutes. (Be careful not to let it get too dark.) Transfer the prime rib to a large carving board.
Make the jus: Carefully pour about 1/2 cup of the pan drippings into a medium saucepan set over low heat. Sprinkle the flour on top and cook, whisking constantly, until the mixture thickens slightly, about 1 minute. Whisk in the beef broth and Worcestershire sauce and bring to a boil over medium-high heat. Lower the heat and simmer, stirring occasionally, until slightly reduced (but not thick like gravy), 3 to 5 minutes. Taste and season, if necessary — the jus should be meaty and pleasantly salty.
Remove the flap with the bones from the prime rib, slicing in between the ribs and the roast to separate the two sections. Thinly slice the roast crosswise and serve the meat and the ribs with the jus on the side.