Grilled mackerel, fennel salad and rocket mayonnaise

Seasonality and sustainability go hand in hand, and that’s never truer than with seafood. You want any fish you eat to be as fresh as feasibly possible and, short of landing it yourself, that means buying whatever is plentiful at any given time of year. And right now, that means mackerel.

We’ve been receiving an abundance of beautiful mackerel this week, all line-caught off the coast of Cornwall, where we work with a great bunch of food heroes who share our values of quality and sustainability. The Wild Harbour Fish Company is a family business that’s been going for more than 30 years. It’s run by Saul and Abi Astrinsky, who work to supply us with wild, sustainably-caught fish that they source entirely from their local fishing fleet in the harbour town of Hayle. They pay their fishermen fairly for the best-quality product they can get their hands on, and every individual shellfish or fillet can be traced back to the individual who caught it.

The produce we receive from them is always of the very best quality, and I’m convinced that, on its day, straight from the boat, you’ll never eat a better, tastier fish than mackerel. Its flavour is supreme, but it’s also a super food, packed with vital fish oils and good omega 3 fatty acids. When it comes to sourcing them yourself for cooking at home, mackerel are most often sold whole, so I’d recommend you ask your fishmonger to fillet it for you. Be sure to ask them to remove the pin bones as well – it’ll save you time as well as effort.

The fatty richness of mackerel can hold its own with a host of different flavour combinations, but I like it best prepared simply as it is here, with the skin perfectly crisped and blackened under the hottest of grills. With that done, a crisp and fresh fennel salad and peppery rocket mayonnaise are all you need to create a perfect, light autumnal dish that will never disappoint.


Chef Patron at Ondine


Serves 4


8 mackerel fillets

50ml rapeseed oil

Salt and pepper, to taste

For the fennel salad

1 green chilli, finely diced

1/2 lemon, juiced

2 heads fennel

A few leaves of flat-leaf parsley

Salt and pepper, to taste

For the rocket mayonnaise

50g rocket leaf

100g mayonnaise

1 tsp lemon juice

Salt and pepper, to taste

1. First up, make the rocket mayonnaise. Prepare a bowl of iced water, then bring a small pan of water to the boil. Plunge the rocket leaves into the boiling water for a few brief seconds, then refresh them in a bowl of iced water.

2. Squeeze all of the excess water out of the rocket, then add it to the bowl of a food processor, add the mayonnaise and blend until smooth. Check and correct the seasoning, add the lemon juice, then spoon into a bowl and set aside.

3. For the salad, slice the fennel bulbs as finely as you can, then plunge into iced water to crispen. After ten minutes, remove the fennel from the water and set it aside on a drying cloth.

4. Once completely dry, transfer to a bowl and mix together with the parsley and diced chillies. Season with lemon juice, salt and pepper then set aside until needed.

5. Heat your grill to a high temperature. Brush the mackerel with a little rapeseed oil and season with salt and pepper, then place under the high grill for a few minutes, until you see the skin start to bubble and crispen up.

6. Remove the mackerel from the heat and set aside, allowing the residual heat of the tray to finishing cooking the mackerel. Season with a splash of lemon juice.

7. To serve, carefully divide the mackerel fillets between four plates. Place a handful of salad onto the tail end of the fish, then spoon the rocket mayonnaise onto the plate before tucking in.

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