Using sharp knife, cut slits in surface layer of fat, spaced 1 inch apart, in crosshatch pattern, being careful to cut down to, but not into, meat. Rub 2 tablespoons salt over entire roast and into slits. Place meat back on bones (to save space in refrigerator), transfer to large plate, and refrigerate, uncovered, at least 24 hours and up to 96 hours.
2
Adjust oven rack to middle position and heat oven to 200 degrees. Heat oil in 12-inch skillet over high heat until just smoking. Sear sides and top of roast (reserving bone) until browned, 6 to 8 minutes total (do not sear side where roast was cut from bone). Place meat back on ribs, so bones fit where they were cut, and let cool for 10 minutes; tie meat to bones with 2 lengths of twine between ribs. Transfer roast, fat side up, to wire rack set in rimmed baking sheet and season with pepper. Roast until meat registers 110 degrees, 3 to 4 hours.
3
Turn off oven; leave roast in oven, opening door as little as possible, until meat register