Slow-roasted Prime Rib Recipe

Bring to cool room temperature

Remove the prime rib from the refrigerator 2 to 3 hours before cooking (at least 90 minutes for smaller roasts). Pat the roast dry with paper towels. Allowing it to warm slightly ensures even cooking.

Season all surfaces of the roast generously with kosher salt and the 2 tbs freshly ground black pepper. Press the salt and pepper into the meat. Place the roast on a rack set inside a rimmed roasting pan and let sit while you prepare the rub (this also dries the surface for better browning).

Prepare the rub

In a small bowl, combine the softened butter, minced garlic, chopped rosemary, chopped thyme, Dijon mustard, olive oil, and 1 tsp coarse ground black pepper. Mix until smooth and well blended.

Using your hands or a spatula, spread the herb-garlic butter all over the exterior of the roast, working into any exposed intercostal fat and crevices. If you prefer a stronger crust, apply an extra thin layer of mustard under the butter before spreading (optional).

Prepare aromatics and roast

Scatter the quartered onion, carrot chunks, celery, and halved garlic in the bottom of the roasting pan around (not under) the rack. Pour 1 cup of beef stock into the pan — this will catch drippings and keep pan fond from burning. Place the rack with the roast on top so the bones are down and the fat cap is up.

Low-and-slow roast

Preheat the oven to 225°F (107°C). Insert an oven-safe instant-read or leave-in probe thermometer into the thickest part of the roast, not touching bone. Roast at 225°F until internal temperature reaches 115°F for rare or 125°F for medium-rare (this typically takes about 20 to 25 minutes per pound at this temperature; for a 6 lb roast, estimate 120–150 minutes). Start checking temperature after 90 minutes. The goal is a slow, even rise in internal temperature.

High-heat sear (reverse sear)

Remove the roast from the oven when it reaches the target 115°F (rare) or 125°F (medium-rare). Increase oven temperature to 500°F (260°C) or set a hot broiler. Let the roast rest uncovered for 10–15 minutes while the oven preheats. Return the roast to the oven and sear for 8–12 minutes, until a deep brown crust forms and the internal temperature reaches 120°F for rare or 130°F for medium-rare. Watch closely to avoid burning.

Rest and carve

Transfer the roast to a cutting board and tent loosely with foil. Rest for 20–30 minutes (rest time will allow carryover cooking and redistribute juices). While resting, reserve pan drippings for au jus or gravy. Carve between the bones into thick slices and serve immediately.

Make quick au jus (optional)

Place the roasting pan over medium heat on the stovetop. Skim excess fat, then add any collected juices and the vegetables. Deglaze the pan with an additional 1/2 cup beef stock or red wine if desired, scraping up browned bits. Simmer 5–7 minutes, strain into a serving vessel, and season to taste with salt and pepper.