4 celery sticks, finely chopped
1 lemon, juice only
500g/1lb 2oz baby new potatoes
1 small bunch flatleaf parsley, finely chopped
150驳/5陆辞锄 radishes, thinly sliced
1 bunch spring onions, thinly sliced
3 tbsp Dijon mustard
6 tbsp mayonnaise
salt and freshly ground black pepper
1 tbsp caster sugar
4 tbsp olive oil
3 tbsp white wine vinegar
16 cooked tiger prawns
3 x 125g/4陆oz middle-cut salmon fillets, skin on