Keep the toro well chilled. Using a very sharp knife, trim away any sinew. Pat the tuna dry with paper towels. Slice the tuna into 1/4-inch (6 mm) cubes or thin 1/8-inch (3 mm) slices depending on preferred presentation. Place on a chilled plate and lightly season with sea salt and a small pinch of black pepper; drizzle the neutral oil over the pieces to add sheen and protect the surface.

Tomato-Soy Dressing

Combine the finely diced tomatoes, light soy sauce, rice vinegar, sesame oil, lime juice, honey (or agave) and grated garlic in a small bowl. Stir and taste for balance: it should be savory with a hint of acidity and a touch of sweetness. Adjust: add a little more soy for saltiness, a few drops of lime for brightness, or honey for sweetness. Let sit 5 minutes to allow the tomato juices to mingle with the soy.

If the tomato mixture seems watery, spoon off excess liquid or strain for a firmer dressing. For a silkier sauce, pulse briefly in a food processor or blender (optional).

Assembly & Serrano Garnish

Spoon a thin bed of the tomato-soy dressing onto each serving plate (about 1 to 1 1/2 tablespoons). Arrange the tuna slices or cubes on top of the dressing in a single layer or slightly overlapping fan.

Scatter the thinly sliced serrano rings over the tuna. Tip: remove seeds if you want milder heat; leave seeds for more punch. Distribute the scallion slices and microgreens or cilantro leaves over the fish.

Finish with a light sprinkle of toasted sesame seeds, a small pinch of black pepper if desired, and a very light dusting of yuzu or lemon zest for aroma.

Serve immediately with extra soy on the side. Encourage diners to take a bit of tuna with tomato dressing and a serrano slice for the intended balance of fatty, salty, acidic and spicy flavors.

Notes

Use the freshest sashimi-grade toro available and keep it cold until serving. All components correspond: tuna (Fatty Tuna section), tomato-soy dressing (Tomato-Soy Dressing section), serrano and garnishes (Serrano-Garnish & Crunch).