Mackerel is one of the best fish to barbecue, and a salad of zingy citrus, chilli and sweet fennel is the perfect accompaniment

M ackerel is one of my favourite fish to barbecue, and when it’s super-fresh it’s hard to beat. With all those omega-3s it’s really good for you, and generally reasonably priced, too. Sardines, bass or grey mullet would work equally well for this dish. Follow my barbecue technique and you won’t overcook the fish or make it stick to the grid.

Serves 4 mackerel 4 large or 8 small, gutted, butterflied and pin-boned lemon 1, cut into wedges, to serve

For the marinade cumin seeds 4 tsp garlic 2 cloves, peeled and finely chopped rosemary leaves 4 tsp, chopped sea salt 2 tsp orange finely grated zest of 1 olive oil 100ml

For the salad red onions 2, peeled and finely sliced red chilli 1, finely sliced white wine vinegar 50ml oranges 2 large or 3 small fennel bulbs 2, tough outer layer removed olive oil 100ml basil leaves 15, finely sliced sea salt and freshly ground black pepper

For the marinade, toast the cumin seeds in a hot, dry pan for a few minutes until fragrant. Tip into a small food processor and add the garlic, rosemary, salt and orange zest. Pour in the olive oil and add a few turns of black pepper. Blitz for 1 minute.

Light your barbecue around 30 minutes before you are planning to start cooking. At the same time, lay the butterflied mackerel on a tray and rub the marinade into the fillets; set aside.

For the salad, toss the red onions and chilli with the wine vinegar and the grated zest and juice of 1 orange; set aside. Cut away the peel from the other orange(s), removing all white pith, then cut out the segments from between the membranes over a bowl, so the segments fall into the bowl; put to one side. Finely slice the fennel using a mandoline if you have one, or a sharp knife. Put the fennel into a large bowl, season with salt and pepper, then add the olive oil and mix well; set aside.

Just before you are ready to cook the mackerel, add the basil and oranges to the fennel salad and toss together, then fold through the red onion mix.

To cook the mackerel, scrape off any excess marinade and carefully lay the mackerel skin side down on the barbecue grid. Don’t be tempted to move it now or you may tear the skin (which is protecting the fish). The flesh will quickly turn from pink to white as it cooks. When each fillet is white three-quarters of the way through, carefully turn it on to a baking tray. Once you have all the mackerel on the baking tray, place it on the barbecue grid for 1 minute to finish cooking.

Serve the barbecued mackerel straight away, with the salad and lemon wedges.

From Nathan Outlaw’s Home Kitchen (Quadrille, £20)

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