Recipe of the week: tuna tataki with salsa verde

The best alternative is yellowfin from the eastern Pacific, where stock is healthy and fishing is well-managed and monitored. To me, yellowfin tuna is equally tasty and actually easier to work with as it comes in a firm, even loin, not dissimilar to a good piece of beef.

I recommend eating tuna in moderation, but really go to town when you do: source the finest quality from the fish market or a reputable fishmonger.

Serves 4-6

700g-800g tuna loin, middle cut

150ml extra virgin olive oil, plus a little extra to coat the fish

Salt and freshly ground black pepper

2g dried wakame seaweed

1tsp wasabi powder

½ bunch flat leaf parsley, finely chopped

½ clove of garlic, finely chopped

1tsp Dijon mustard

2tbs mirin

40g drained capers, finely chopped

Green beans

Sugar snap peas

Mustard miso

Prepare the tuna loin on a chopping board: cut away the sinew part of the loin, which constitutes the belly flap on a yellowfin tuna (store this in the fridge and scrape out the tuna with a spoon when needed, to use in another recipe).

Divide the loin into rectangular logs about 2.5cm in diameter; you should get between four and six blocks out of the loin. Pour a little olive oil into a shallow tray and season with salt and pepper. Roll the loins in the oil, ensuring they are well coated, and set aside in the fridge, covered.

Now for the salsa verde. Dilute the wakame in 500ml cold water and leave for 10 minutes. Mix the wasabi powder with a little water to make a paste. In a bowl, combine the parsley, garlic, wasabi paste, mustard, mirin, capers and olive oil. Drain and chop the wakame and add to the bowl, then set aside.

Start the robata grill. When it is ready, grill the tuna on a wire rack for less than a minute on each side, so it is evenly seared. With a very sharp cook's knife or sashimi knife, slice the tuna into 5mm-thick slices, starting from the heel of the knife and pulling the knife towards yourself in one even movement, to avoid sawing through the protein and tearing the flesh.

Arrange the tuna slices along the length of the serving dish, overlapping one another. Spoon a little salsa verde on top and serve with green beans and sugar snap peas with mustard miso.

• Recipe taken fromRobata: Japanese Home Grilling by Silla Bjerrum

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