Bring meat to room temperature: Remove prime rib from the refrigerator one hour before cooking. Season it on all sides with salt and cover it loosely with plastic wrap as it comes to room temperature. Prime rib roast will cook better and more evenly when it’s at room temperature.

Adjust oven racks: When you are ready to cook the prime rib, lower/adjust your oven rack so the meat will cook in the center of the oven. Preheat the oven to 500 degrees F.

Combine seasonings: In the meantime, mix together 1 1/2 teaspoons salt, pepper, rosemary, thyme, garlic, and olive oil.

Prepare roast: Pat the roast with paper towels. Spoon seasoning over it, rubbing it onto all sides. Place bone-in roast with the bones down, inside a roasting cast iron pan. Place a boneless roast on a rack inside the pan.

Bake prime rib at 500 degrees for 15 minutes, then reduce the oven temperature to 325 degrees and continue baking until desired level of doneness. Use a meat thermometer to check the temperature of the meat:Rare: 120 degrees F (about 10-12 min/pound). Medium Rare: 130 degrees F (about 13-14 min/pound)Medium: 140 degrees F (about 14-15 min/pound)Medium Well:150 degrees FImportant: The meat will continue to cook as it rests out of the oven so remove it from the oven 5-10 degrees before it reaches your optimal temperature.)

Rest: Remove it from the oven and tent it with foil. Allow it to rest for 30 minutes before carving.

Carve prime rib roast by slicing against the grain into about 1/2 inch thick slices. Serve with horseradish, if desired.