Roast in a 325 degree F oven to desired doneness. [Allow 2 to 2-1/2 hours for rare (140 degrees F) or 2-1/4 to 3-1/4 hours for medium (155 degrees F.] Transfer meat to a cutting board. Cover with foil and let stand for 15 minutes before carving. (The temperature of the meat will rise 5 degrees during standing.) If desired, garnish with additional fresh rosemary.