Clean pork shoulder with lime, rinse with cold water and pat dry. Using a sharp knife, score the surface of the meat with small but deep slits. Place pork shoulder in a large bowl. In another bowl, mix all ingredients and 6 tablespoons of jerk seasoning. Pour jerk mixture over pork shoulder and make sure that some of the spices go inside the slits. Cover pork with plastic wrap and marinate in the refrigerator for at least 10 hours or overnight.

Allow the meat to sit at room temperature for 30 minutes before cooking. Preheat oven to 180ºC / 350ºF / Gas Mark 4. Remove pork from marinade and pat dry. Rub the remaining 2 tablespoons all over the meat and place fat side up in a roasting pan fitted with a rack insert.

Roast meat for 2 hours. Lower heat to 160°C / 325°F / Gas Mark 3 and continue to roast for 1 hour and 50 minutes until a meat thermometer inserted into the center registers 85°C / 185°F for well-done and the skin is crispy brown. Let the roast rest before slicing.