In a large bowl, combine the soy sauce, lime juice, ground black pepper, garlic powder, and hot sauce. Mix well.
Put the cleaned pork belly in a large resealable bag. You can slice the pork belly thinner so that it can quickly absorb the marinade.
Pour the soy sauce mixture in the resealable bag. Let all the air out then seal. Let the pork belly marinate for at least 1 hour. You can place the bag in the refrigerator during the process.
Heat-up the grill. Start to grill the marinated pork belly for 3 minutes per side. Baste the pork belly with the remaining marinade. Note: Do this process at least 3 times. This means that each side of the pork belly is grilled for a minimum of 9 minutes (3 minutes x 3 times). This will prevent the pork from getting burnt quickly. Make sure that you baste it every time you flip it over. Grill longer if the pork belly is not cooked enough.
Remove the pork belly from the grill. Let cool. Slice into serving pieces.
Serve with spicy vinegar. Share and enjoy!