Cut the pork shoulder into cubes about one inch in size all around. Add the meat in an air-tight container larger than the amount of meat inside, leaving room for the marinade.
In a large mixing bowl, combine the banana ketchup, 7-up, soy sauce, vinegar, oyster sauce, chili oil with black bean sauce, brown sugar, ground pepper, and garlic. Whisk the contents and make sure the brown sugar has dissolved.
Pour the marinade over the meat and mix together to make sure all the meat is covered. Marinade for six hours and no more than eight hours, refrigerated.
Soak the bamboo skewers in water for at least 30 minutes. Remove the marinade from the fridge and let sit on the counter for 30 minutes to adjust the temperature before grilling (this is also easier on your hands when skewering).
In a small bowl, combine the banana ketchup, oyster sauce, and sesame oil and mix thoroughly.
Assemble the BBQ skewers by adding about five-six pieces of pork to each skewer. Try to alternate fattier and leaner pieces. Repeat until all pieces of meat are skewered.
Preheat the grill to medium-high heat (about 80%). Place the skewers on the grill and cook for four minutes on one side before turning. Repeat cooking for another four minutes.
Use a brush to baste the glaze on one side of the skewer, turn over the skewer, cook for one minute. Repeat basting and cooking. Check the temperature of the meat to see if it’s cooked thoroughly (145 °F). You can also use a knife to cut a piece of pork and check the center. Finish pork skewers should be slightly firm, but not dry and not translucent in the middle. Adjust cooking time if necessary or remove the skewers if they’re finished.
Serve with a side of rice and sweet Filipino pickles.