Ingredients
- For the Mustard and Herb Butter:
- 4 ounces (1/2 cup or 1 stick) unsalted butter, cut into chunks
- 6 medium cloves garlic
- 1/4 cup loosely packed fresh rosemary leaves
- 1/4 cup loosely packed fresh sage leaves
- 1/4 cup loosely packed fresh thyme leaves
- 1/4 cup Dijon mustard
- 1 tablespoon Worcestershire sauce
- Kosher salt and freshly ground black pepper
- For the Prime Rib:
- One 5- to 6-pound boneless beef rib roast, patted dry
- 2 tablespoons olive oil, if needed for searing
Directions
- Melt the butter in an 8-inch skillet over medium heat. Let it foam until it turns light brown and smells nutty, about 5 minutes. Immediately pour the butter into a small heatproof bowl, leaving most of the milk solids in the bottom of the skillet. Refrigerate the butter until solid, about 1 hour (or freeze, to speed this up).
- Purée the garlic, rosemary, sage, thyme, mustard, Worcestershire, 1 1/2 teaspoons salt, and 1 teaspoon pepper with the solidified browned butter in a food processor to make a thick paste. Reserve 1/4 cup of the butter and rub the rest all over the roast. Put the roast fat side-up on a rack set in a roasting pan and let sit at room temperature for 1 hour before roasting.
- Position a rack in the center of the oven and heat the oven to 300° F. Roast the beef until an instant-read thermometer registers 110° F for rare, about 1 1/2 hours, or 115° F for medium rare, about 10 minutes more. Remove the roast from the oven. Let sit, tented loosely with foil, for up to 2 hours (or continue with the recipe).
- To sear in the oven: Heat the oven to 475° F. Roast until 125° F for rare or 130° F for medium rare, about 10 minutes.
- Or, to sear on the stove: Heat the oil in a heavy 12-inch skillet until shimmering hot. Sear the beef, turning and pressing down with tongs, until browned all over and cooked to desired temperature, about 4 minutes per side. Transfer to a cutting board. If there was no earlier rest between roasting and searing, let the roast rest for 15 to 20 minutes. Slice and serve with the reserved mustard butter.
- The beef can be roasted and then sit at room temperature, tented with foil, for up to 2 hours before the final sear.