1 head white radicchio, leaves torn into bite-sized pieces
150驳/5陆辞锄 shallots, finely chopped
sea salt flakes and freshly ground black pepper
75驳/2戮辞锄 caster sugar
125驳/4陆辞锄 currants
3 tbsp hazelnuts, roasted
4 tbsp olive oil
120ml/3戮fl oz extra virgin olive oil
375ml/13fl oz white wine vinegar
2 whole mackerel, butterflied
150ml/5fl oz white wine