Pierce the pork all over and rub in the 2 teaspoons salt and 2 tablespoons orange juice. Set aside while you prepare the seasoning paste. Grind the achiote seeds, cumin, oregano, peppercorns and allspice together to a fine powder. Crush the garlic together with the chile seco, salt and 3 tablespoons Seville orange juice and mix with other powdered spices. The mixture should be a thick paste. Coat the pork with the paste. Lightly sear the banana leaves over a bare flame to make them more flexible. Wrap the meat up in them and leave to season in the refrigerator for at least six hours or overnight. ON SERVING DAY: Preheat oven to 325 degrees. Place a rack at the bottom of the Dutch oven and cover the dish with a tight fitting lid. Cook for 2 1/2 hours. Turn the meat and baste it well with the juices at the bottom of the pot. Cook for another 2 1/2 hours, or until the meat is soft and falling off the bone. Meanwhile, prepare the salsa: mix all ingredients together. Set aside to season for about 2 hours. Serve in a separate dish. After cooking, shred the meat roughly. Pour the fat and juices from the pan over it. Serve hot, with tortillas and the sauce so that each person can make his or her own tacos. NOTE: A rough approximation of Seville orange juice may be attained through the following: For 1/2 cup blended juice, combine 1 teaspoon finely grated grapefruit rind, 3 tablespoons orange juice, 3 tablespoons grapefruit juice and 2 tablespoons lemon juice. Recipe from _The Cuisines of Mexico_ by Diana Kennedy Recipe By :