Thinly slice the onion. Julienne the cucumber by first cutting on the diagonal, then slicing into matchsticks. Cut the daikon similarly into matchsticks. Roughly chop the radish sprouts into 3 cm sections.
Soak the prepared vegetables from Step 1.
Chop seared skipjack tuna (bonito) into bite-sized pieces.
Thoroughly drain the excess water from the vegetables and add to the seared tuna from Step 3. Combine all seasoning ingredients and drizzle over vegetables and tuna as a dressing.
Story Behind this Recipe
I came up with this recipe when I didn't have enough seared tuna to go around, and now, it's something I make often. It looks nice served in a large dish, so it also makes a good dish to serve guests.
Chinese chives, myoga, shiso (perilla) leaves, and lettuce also go well with seared tuna. You can use this dressing for any kind of salad. Substituting garlic with grated ginger is also delicious.