Note: This is best marinated overnight, so give yourself the extra time!
Rinse off the pork and pat it dry. Slide a sharp knife under the skin around the roast to separate it slightly in a few places, making “pouches.” (Be careful not to remove the skin from the meat entirely.) Lightly score the top of the fat in a crisscross pattern.
Mix the remaining ingredients by hand or in a blender to form a paste. Season the insides of the pockets with the paste and rub the remaining paste all over the pork. Place on a roasting rack, cover the pork with foil, and refrigerate overnight for best flavor.
When ready to cook, preheat the oven to 325°F. Remove the pork from the refrigerator and let sit for 15-20 minutes.
Cook, covered, for 30 minutes per pound at 325°F. Raise the temperature to 425°F, remove foil, and cook an additional 30 minutes, until the skin becomes crispy. If desired, you can do a quick broil for extra-crispy skin, but watch carefully to prevent burning. Remove from the oven and let sit for at least 20 minutes before cutting.