Adjust oven rack to low position and preheat oven to 200 degrees F. Heat a large roasting pan over 2 burners set at medium-high heat. Place roast in hot pan and sear on all sides until nicely browned and about 1/2 cup of fat has rendered, 6 to 8 minutes.
Remove roast from pan. Set a wire rack in pan; set roast on rack. Generously season meat with salt and pepper.
Place roast in oven and roast until a meat thermometer registers 130 degrees for medium-rare, about 3 1/2 hours. If roast is done sooner than you expect, simply turn oven as low as possible (preferably 150 to 170 degrees F) and let stand until ready to serve.
Transfer roast to a cutting board, with rib bones perpendicular to board. Using a carving fork to hold roast in place, cut along rib bones to sever meat from bones. Set roast cut side down and carve meat across grain into 3/4 to 1-inch-thick slices. Serve immediately.