In a bowl, add minced garlic, light soy sauce, dark soy sauce, fish sauce, oyster sauce, brown sugar, white pepper and water. Mix well. Add the sliced pork and mix thoroughly once more. Cover and set aside in the fridge for at least 4 hours or, ideally, overnight.
Heat the oven to around 80c - if the lowest oven setting available is gas mark 1, leave the oven door open a little. Brush a grill tray with a touch of oil and arrange the pork slices evenly on the rack. Place in the oven and cook for 1 hour and 20 minutes.
Heat the oil for deep frying to 180c. Transfer all of the pork slices into the hot oil and fry for 1-2 minutes or until golden. Drain off any excess oil, arrange the pork on a serving plate and top with spring onions and a few more toasted sesame seeds.