1 heaped tbsp freshly chopped dill, plus extra to garnish
陆 lemon, finely grated zest and 1 tbsp juice only
陆 tsp finely grated lemon zest
1 heaped tbsp freshly chopped tarragon, plus extra to garnish
2 tsp Dijon mustard
freshly ground black pepper
2 tsp extra virgin olive oil
2 tbsp extra virgin olive oil
flaked sea salt, to taste
50ml/2fl oz sunflower oil
2 large egg yolks
2 tbsp Greek yoghurt
2 fillets fresh mackerel (each around 100g/3陆oz), pin-boned and cut in half lengthways to make 4 fillets
warmed sourdough or soda bread, to serve