Remove the pork from the refrigerator 1 hour before you want to cook it, to let it come up to room temperature.
Preheat the oven 425°F
Place the pork on a clean work surface, fat-side up. Score the fat ½ inches apart, going mostly through the fat but not into the meat.
Rub sea salt right into the scores you’ve just made, pulling the fat apart as needed. Brush any excess salt off the surface then turn it over. Season the underside of the meat with salt and pepper.
Place the pork, fat-side up, in a roasting pan and roast for 30 minutes, or until the fat is puffing up and starting to turn golden (it will render and darken more later). At this point, turn the heat down to 325°F. Cover the pork tightly with a layer of tin foil, put back in the oven and roast for another 4½ hours.
Remove the pork from the oven, take off the foil, and baste the meat with the fat in the bottom of the tray. If there are excess juices in the pan you can drain them now (consider saving to make stock).
Place the pork back in the oven without the foil to roast for another hour, or until meltingly soft and tender.
I am not a health professional and nutrition data is calculated programatically. Accuracy may vary with product selection, calculator accuracy, etc. Consult a professional for the best information.