Very finely mince 250g fresh tuna. Place in a small bowl with a drizzle of soy sauce. Mix well and then roll into 6 balls and then flatten into burger shapes. Fry or grill for around 2 minutes on each side.

Meanwhile, mix together 3 tbs good-quality mayonnaise with 2 tsp soy sauce, 2 tsp yuzu juice (a Japanese citrus fruit), 2 tsp mirin, 1 tsp wasabi powder and 1 tbs ketchup.

Serve the burgers in mini-buns with a dollop of mayonnaise and a side salad of lamb’s lettuce with a Japanese sesame dressing.

Serves 2.