Heat the oil in a saucepan large enough to take the fish. Add the garlic and fry until dark brown. Remove the garlic and lay the fish in the hot oil. Sprinkle with salt and pepper and a little vinegar. Cook for 5 minutes, spooning the hot oil over the fish.
Pour in enough water to come halfway up the fish. Continue cooking for 10–12 minutes or until the fish is cooked through. Serve hot