Dehydrate the ‘nduja for 72 hours in a dehydrator set at 85ºC. It’s best to do this in a colander over a bowl so you keep the oil. Once the ‘nduja is completely dry, store in an airtight container for later

Bring a pan of salted water to the boil. Boil the pork rind for 3 minutes then drain, press flat and chill in the fridge to allow the fat to set

Once the pork skin is chilled, scrape all the excess fat away and dehydrate the pork skin at 85ºC for around 24 hours (it can go in with the ‘nduja)

Once the pork skin is completely dry, preheat an oven to 220°C/gas mark 7. Bake the rind for 6–8 minutes until it turns crispy and puffs up (about ). Crush the skin into a crumb and reserve

Slice the cucumber as thinly as possible using a mandoline and place the slices in a heatproof bowl. Toast the mustard seeds in a hot dry saucepan, then add the rest of the pickle ingredients and bring the mixture to a boil. As soon as it reaches a boil, pour it over the cucumber and leave to cool

Trim the mackerel fillets and score lines into the skin. Mix together the ingredients for the mackerel cure, then submerge the mackerel in the mixture and leave to cure for 20 minutes

Remove the fillets from the cure, pat dry thoroughly and blowtorch the mackerel skin until black (alternatively you can put the mackerel skin-side up under a hot grill)

To serve, divide the mackerel fillets between 4 plates. Dress with the cucumber on top, followed by crumbled 'nduja and pork skin