Separate roast from rib bones (you can ask your butcher do this).
Trim fat cap but leave a layer of fat (you can also ask your butcher to do this). Use a knife to slice slits into the fat cap in a crosshatch pattern. Cut though the fat but not the meat. Season liberally with kosher salt all all over the surface of the meat.
Place roast back on the bones. Set roast on a sheet pan fitted with a rack in the fridge for at least 24 hours up to 3 days, uncovered.
Preheat oven to 225 F (if using a convection oven, use 200 F).
Heat a large skillet with oil over medium high heat. Brown the sides and top of the roast. After browning, place roast back on to bones and tie together with kitchen twine. . Season with pepper if desired.
Set on a rack fitted to a baking sheet and roast uncovered until internal temp registers 110 degrees - this should take about 3-4 hours. Turn off the oven. Let it sit in the oven uncovered until internal temp hits 115 for rare, 120 for medium rare. (temperature will continue to rise after removing from the oven. Broil if desired. After removing from the oven rest for 30 minutes loosely tented with foil.
After resting, remove roast from bones for easy carving. Slice the ribs and slice roast into 3/4 inch slices. Season slices with salt before serving.