Soak the salt cod in cold water for 24 hours, changing the water five times. Drain, then discard any skin or discoloured meat and roughly chop the remainder.
Bring a heavy-based saucepan of water to the boil and add the potato, then cook for 20 minutes or until very soft. Remove from the heat, add the salt cod to the pan, then cover and set aside.
Place the olive oil and water i