1. Remove the skin and most of the fat. Place the meat on a board, score all over and butterfly where necessary to ensure the meat is even and levelled out. Rub with oil, salt and garlic. Mix the rub ingredients together and rub all over the meat.
2. Get a fire going, put the coals in the very bottom and once ready, add a large handful of wood chips and a pinch of tea leaves for smoky effect. Place the lower grill on. Place a loaf tin filled with water to one side of the lower grill.
3. Place the main grill on and place the pork in the middle over the direct heat of the coals. Put the lid on and open the vents slightly. Braai the meat and after 30 minutes turn the pork for another 30 minutes on the other side. Turn it again for another 30 minutes and now top up the coals and the water if necessary.
4. Repeat the turning, cooking the pork for 3 hours in total. Remove the pork and get it into a large cast pot with a lid.
5. Mix the barbeque sauce, water, mustard and white wine vinegar together in a jug. Pour half the mixture over the meat, put the lid on the pot and place in a preheated 140°C oven for another 3 hours, adding the remaining sauce half way though the cooking. Remove from the oven and rest for 15 minutes to cool down slightly. Remove the meat and shred using two forks. Then return the meat to the pan and mix with the pan juices and mix together.
6. To make the sliders, cut the buns in half and toast each side until slightly crispy. Top the bottom side of the bun with mustard, mixed salad leaves, followed by shredded pulled pork, gherkins, shredded cabbage and pickled onions and the top half of the bun. Secure with a short wooden skewer. Repeat with remaining buns and place on large platter and serve.