Combine soy sauce, banana ketchup, lemon juice, salt, pepper, garlic powder, and brown sugar in a bowl. Mix well. You can also microwave the mixture for 1 minute (optional). This will melt the sugar and make it easier for the other ingredients to dilute quickly.
Arrange the sliced pork in a resealable bag or in a bowl. Pour-in the soy sauce mixture. Make sure that the mixture is in room temperature.
Massage the pork slices and make sure that it is completely soaked in the soy sauce mixture. Seal the bag or cover the bowl. Place inside the refrigerator and marinate for at least 5 hours.
Skewer the marinated pork slices in a bamboo skewer (this is also known as barbecue stick).
Heat-up the grill. Grill each skewered pork for 5 minutes per side in medium heat. Brush some basting sauce on each side before turning it over. Do this cycle twice or until the pork is fully cooked.
Transfer to a serving plate. Serve with vinegar dip.
Share and enjoy.