Slice fluke against the grain into ¼ inch slices, then cut into ¼–½ inch strips. Set aside.

In a small bowl, combine yuzu kosho, calamansi vinegar, and a pinch of kosher salt. Transfer mixture to a small squeeze bottle and shake well to combine.

Drizzle in half the olive oil, close, and shake the squeeze bottle. Add the remaining olive oil and shake again to emulsify.

Arrange the fluke slices spaced out on a serving plate.

Drizzle the calamansi vinaigrette evenly over the fish.

Finish with a drizzle of high-quality extra virgin olive oil, a sprinkle of flaky Maldon salt, and garnish with thinly sliced chives.