1, 6-8 pound prime rib
3-4 teaspoons salt
3-4 teaspoons black pepper
3-4 teaspoons granulated garlic
¼ cup fat trimmed from the prime rib
2 tablespoons flour
2 cups beef stock
¼ teaspoon salt
¼ teaspoon black pepper
Preheat oven to 300 degrees.
Rub the beef all over with the salt, pepper, and garlic. Place in a large roasting pan. Bake for 2-2 ½ hours until the internal temperature reaches 115 degrees (it will continue to cook while it rests).
Remove from the oven, tent with foil, and let rest for 30 minutes.
To make the au jus, drain ¼ cup of the fat from the pan after cooking the beef (or use fat trimmed from the roast before cooking). Heat the fat in a large saucepan. Whisk in the flour, salt, and pepper. Add the beef stock and bring to a boil. Let cook for 3-4 minutes, whisking frequently, as it thickens slightly. Keep warm until ready to serve.