– 2 large pinches of coriander seeds
– 120ml balsamic vinegar
– 120ml Chardonnay vinegar
– 4 tbsp light soft brown sugar
– 4 whole mackerel, around 250g each, heads removed, filleted and skin lightly scored
– 1 tbsp sea salt
– 1 small red onion, finely sliced
– 2 coriander (cilantro) sprigs, plus 2 tbsp chopped coriander leaves
– 1 garlic clove
- Heat a frying pan over a medium heat. Add the coriander seeds and lightly toast for 1 minute, shaking the pan occasionally, until they colour slightly and smell aromatic. Tip them onto a plate and lightly crush with the blade of knife. Leave to one side.
- Pour both vinegars into a small saucepan. Add the sugar and put over a medium heat to warm for 2-3 minutes, or just long enough for the sugar to dissolve, stirring occasionally. Remove from the heat, stir in the toasted coriander seeds and leave to cool.
- Put the mackerel in a shallow, non-metallic dish, skin-side down, and sprinkle with sea salt. Pour over the cold vinegar mixture and top with three-quarters of the red onion. Cover with cling film and leave to marinate in the fridge for about six hours until pickled, turning the fish halfway through.
- Lift the mackerel out of the pickling liquor and put on serving plates. Scatter some of the red onion over the top and serve with the potato salad.