Remove your prime rib from the refrigerator 3 hours before cooking to bring it to room temperature. This ensures even cooking throughout the roast.
Preheat your oven to 450°F (230°C).
In a bowl, combine minced garlic, rosemary, thyme, sage, olive oil, and Dijon mustard to create a paste.
Pat the roast dry with paper towels, then generously season all sides with kosher salt and black pepper.
Spread the herb paste evenly over the entire surface of the meat, pressing gently to adhere.
Place the roast bone-side down in a roasting pan with a rack.
Sear the roast at 450°F for 15 minutes to develop a crust.
Reduce the temperature to 325°F (165°C) and continue cooking for about 15 minutes per pound for medium-rare, or until internal temperature reaches 120-125°F.
Remove from oven and tent with foil. Let rest for 20-30 minutes before carving.