1. Place a rack in lower-middle of oven and heat to 250 degrees. Pat meat dry with a paper towel and season all over with salt, pepper, and rosemary.
2. Transfer meat, fat-side up, to a rimmed baking sheet fitted with a wire rack. Roast until meat registers 120 degrees for medium-rare, 3 to 4 hours. Remove from oven, tent loosely with foil, and let rest at least 30 minutes and up to 1 hour.
3. To serve, increase oven temperature to 450 degrees. Return meat to oven and cook until a dark-brown crust develops, 10 to 12 minutes. Transfer to a cutting board and remove twine and ribs before carving.
Source: Hannaford fresh Magazine, November - December 2016