In a small bowl, combine vinegar, salt, pepper and chopped garlic. Stir well to combine.
Place the thawed bangus (skin side up) in a long 9x13 glass pyrex pan (non-reactive) and pour the vinegar mixture over it, making sure to coat the fish well. Marinate in the fridge for at least 2 hours or overnight.
Place about 1/2 inch cooking oil in the frying pan. Turn the heat to medium until oil is hot enough for frying. Test the heat by placing a wooden chopstick/back of a wooden spoon in the oil. If it bubbles around the wood, it’s ready. Cook the fish for 6-10 minutes (depending on the size) flipping halfway or until each side is golden. Drain on a paper towel-lined plate to absorb excess oil.
Serve with atchara (pickled green papaya) or any dipping sauce of your choice. Best served with any vegetable dish like Pinakbet.