Use hot oil for best results. This will ensure a crispy outside with a moist inside. Do not fry too slowly, as the fish will be limp and pale and might fall apart. Cover base of pan with oil. Butter adds flavour, but because it can burn, add a little oil. The frying time can vary from 6 – 8 minutes depending on thickness of the portion. To establish when the oil is ready for frying, dip a cube of bread in the oil. It should turn light brown in 90 seconds.