Sardines in saor

Method

1. Put the raisins, if using, in a bowl of warm water and leave to soak for 20 minutes. Heat the extra-virgin olive oil in a saucepan over a low heat. Cut the onions into thin half-moons and add to the pan with a pinch of salt. Cook for 10-15 minutes until soft but not coloured. Add the pine nuts and raisins, if using (use neither or both), and remove from the heat. When cool, add the vinegar.
2. Season the sardines with salt and lightly dust in some flour. Heat the olive oil in a pan over a high heat and fry the sardines in batches for 2 minutes on each side. Their skin should colour a little, but the flesh should still be raw near to the bone.
3. Place the fish in a large dish, in a single layer, with the onions and vinegar. Cover and chill for at least a day (if possible 2-3 days) before eating. You will need to turn the fish once or twice in the marinade.