small handful finely chopped fresh dill, plus extra to serve
1 garlic clove, finely grated
40g/1½oz cornichons or gherkins, finely diced
350g/12oz new potatoes, large ones quartered and smaller ones halved
small handful finely chopped fresh parsley, plus extra to serve
40g/1½oz red onion (approx. ½ small onion), finely diced
large handful (approx. 60g/2¼oz) baby spinach (or rocket, spinach and watercress mix)
1 tsp Dijon mustard
50g/1¾oz mayonnaise
sea salt and freshly ground black pepper
1 tsp runny honey
2 tbsp olive oil
1 tsp white wine vinegar
50g/1¾oz soured cream
2 smoked mackerel fillets (approx. 175g/6oz), skin removed and torn into bite-sized pieces