Barbecued mackerel with tomato & olive dressing

To make the dressing, score a cross in the bottom of each tomato, then put in a large heatproof bowl. Pour over boiling water from the kettle to completely cover, then leave for 30 seconds until the skin starts to curl. Drain and put in cold water to cool a little. Drain again, then peel away the skin. Quarter and deseed the tomatoes, then finely chop. Set aside.

Heat the olive oil and coriander seeds together in a deep-sided frying pan until starting to sizzle, then stir in the garlic and leave for 1 min to infuse. Pour about 2 tbsp of the oil into a smaller pan, then tip the rest of the oil into a bowl with the tomatoes, olives, lemon zest and juice, the parsley and basil. Season, mix well and set aside. Will keep for a few hours at room temperature, but add the herbs just before serving.

Light the barbecue and wait until the coals are ashen. Meanwhile, lay half of the rosemary over a fish cage. Brush the mackerel with some of the reserved olive oil and season with sea salt flakes. Lay the fish on the rosemary, drizzle over the rest of the oil, tuck in the remaining rosemary, and close the cage. Once the coals are grey and the heat emitted isn’t too severe, grill the mackerel for about 5 mins on each side until the skin blisters and the flesh is cooked through. Remove the mackerel from the cage. Serve on a platter with the dressing spooned over.