• Preheat the oven to 450°F and cover a baking sheet with foil for easy clean-up.

Prepare the rack of lamb:

• With a sharp knife, lightly score the fat cap on the meaty top side of the rack, diagonally, in slits about 1-inch apart. Do not cut deep into the meat.

For the Garlic Rosemary Mixture:

• In a small dish add the garlic, rosemary, olive oil, salt and pepper and combine by mashing together with the back of a tablespoon.
• Spoon the garlic rosemary mixture onto the scored lamb and using your (clean) hands, spread the mixture evenly over the lamb, working into the slits. 

To Roast the Rack of Lamb:

• Place the lamb rack, meaty side up with rib bones on the baking sheet.
• Transfer the lamb rack to the oven on a rack position in the upper third. Roast for 20 minutes to an internal temperature of 135°F for medium rare. A meat thermometer should be inserted in the thickest part of the meat for an accurate reading.
• Transfer the rack of lamb to a carving board and let them rest for 5 to 10 minutes. 

To Carve and Serve the Rack of Lamb:

• Grasp the ends of the bones and stand the meat up on end. Slice between the rib bones and transfer to a platter or on warm serving plates. 
• Garnish with fresh rosemary sprigs.