Put pork liempo in a bowl or any plastic container that will fit the 1 kilo pork.
Add calamansi juice, garlic, black pepper, barbecue marinade, ketchup and 1 tablespoon cooking oil.
Mix all the ingredients and gently massage the pork belly then marinate for one hour or overnight in the refrigerator.
To cook the liempo, heat 3 Tbsp. of cooking oil in a frying pan. Drain the pork liempo with a colander and reserve the marinade for later use.
Fry the pork in the pan until brown on all sides. Then pour the marinade in the pan and let it boil.
Cook in low heat until the sauce is reduced while turning or flipping the pork from time to time to avoid burning,
Cook until the sauce is almost dry and oil renders from the pork.
Serve hot with cooked rice.