Preheat your oven to 450°F (230°C). Place the prime rib roast on a rack in a roasting pan. Rub the roast all over with olive oil, then evenly spread minced garlic, chopped rosemary, salt, and pepper over the surface, pressing gently to adhere.
4 lb prime rib roast, 3 cloves garlic, 2 tablespoons olive oil, 1 tablespoon fresh rosemary, 1 tablespoon kosher salt, 1/2 teaspoon black pepper
Insert a meat thermometer into the thickest part of the roast. Transfer the pan to the preheated oven and roast for about 15 minutes to develop a crust that is golden and fragrant.
After the initial high-temperature roast, reduce the oven temperature to 325°F (160°C). Continue roasting until the internal temperature reaches 125°F (52°C) for medium-rare, about 45-60 minutes depending on size.
Once the desired temperature is reached, remove the roast from the oven, tent loosely with foil, and let it rest for 20 minutes. During resting, the juices redistribute, and the internal temperature will rise slightly.
Uncover the roast, and transfer it to a carving board. Slice against the grain into thick, juicy portions, revealing a rosy, tender interior and a crackling crust.
Serve immediately with your favorite sides, enjoying the rich aroma and perfectly cooked tenderness of the prime rib.