Prime Rib with Guinness Au Jus

1 (5-7 pounds) prime rib roast
8 cloves garlic, minced
2 tablespoons olive oil
2 teaspoons salt
2 teaspoons ground black pepper
2 teaspoons dried thyme
1 can of Guinness beer 
  1. In a small bowl, mix together the garlic, olive oil, salt, pepper and thyme. 
  2. Place the roast in a roasting pan, fatty side up.  Make shallow cuts in the roast to allow for better marination.
  3. Spread garlic mixture over the fatty layer of the roast, and let roast marinade and sit out until the roast is at room temperature, which is about a 1 hour.
  4. Preheat the oven to 450 degrees F.
  5. Bake the roast for 20 minutes in the preheated oven. This will create the crisp and cooked crust of the roast while keeping the inside of the meat juicy and tender.
  6. Then reduce the temperature to 325 degrees F, and continue roasting for an additional 60 to 75 minutes (the meat will take about 10-15 minutes per pound). 
  7. Remove roast when the internal temperature of the roast should be at 140 degrees F for medium rare.  Using a meat thermometer would be very helpful here. 
  8. Allow the roast to rest in room temperature for 15 minutes before carving so the meat can retain its juices.
  9. After moving the roast onto a serving plate, make the au jus dip by pouring the can of Guinness in the roasting pan and mix well with the roast drippings.  Pour the mixture into a serving bowl.