Ahi Tosa Recipe

Prep Tuna

Pat the ahi tuna dry with paper towels. Season all sides lightly with kosher salt and freshly ground black pepper.

Heat Pan

Heat a heavy skillet or cast-iron pan over high heat until shimmering (about 2–3 minutes). Add 2 tbs neutral oil and swirl to coat.

Sear

Place the tuna in the hot pan and sear for 20–30 seconds per side for a rare center (adjust 45–60 seconds for medium rare). Do not cook through — the inside should remain pink. Remove from pan and let rest 2 minutes.

Slice

Using a very sharp knife, slice the tuna across the grain into 1/4-inch thick slices. Arrange slices on a serving platter or individual plates.

Whisk together 3 tbs dark soy sauce, 1 tbs mirin, 1 tbs brown sugar, 1 tsp grated ginger, 1 tsp minced garlic, and 1/2 tsp toasted sesame oil in a small bowl until sugar dissolves. Taste and adjust sweetness or salt as needed. Set aside.

Optional (warm glaze): Warm the sauce gently in a small saucepan over low heat for 1–2 minutes to meld flavors, then cool slightly before using.

Have 2 tbs unagi sauce and 2 tbs ponzu ready. You will use unagi sauce for a sweet glazed streak across the tuna and ponzu to add bright citrus finish.

Combine 2 tbs soy sauce, 1 tsp finely minced garlic, 1/2 tsp sugar, 1/2 tsp rice vinegar and 1 tsp vegetable oil in a small bowl. Stir until sugar dissolves. This will be a savory drizzle; keep it room temperature until plating.

If you prefer a milder garlic flavor, briefly warm the mixture (10–15 seconds) in the microwave to soften raw edge, then cool slightly.

If using dried wakame, rehydrate it in warm water for 5–7 minutes, then drain well and squeeze out excess water. Chop or tear into bite-sized pieces to measure 1/2 cup when drained.

In a small bowl toss the drained wakame with 1/4 cup julienned cucumber, 2 tbs sliced scallions, 1 tsp toasted sesame seeds and 1/4 tsp red pepper flakes (if using). Dress lightly with 1/2 tbs ponzu or 1 tsp of the Hawaiian sauce if you like — toss to combine.

Taste and adjust: add a squeeze of lemon or lime if more brightness is desired.

Place a small mound of wakame salad at one end or in the center of the plate beside the arranged tuna slices.

Drizzle the Hawaiian sauce lightly over the tuna slices (about 1–2 tbs total), then add a few thin lines or dots of unagi sauce for sweetness and ponzu for citrus brightness. Use the soy-garlic mixture sparingly as an additional drizzle or in a small dipping pool.

Scatter remaining sliced scallions and toasted sesame seeds over the tuna. Serve immediately with lemon or lime wedges on the side so diners can add a final squeeze if desired.