Sliced Ahi Tuna Recipe

Prepare tuna

Pat the tuna loin dry with paper towels. Season all sides lightly with kosher salt and black pepper, then press the blackened seasoning evenly onto all surfaces so the tuna is well coated.

Heat pan

Heat a heavy skillet or cast-iron pan over high heat until very hot (2–3 minutes). Add 2 tablespoons olive oil and swirl to coat; oil should shimmer but not smoke heavily.

Sear tuna

Place the seasoned tuna in the hot pan. Sear for 45–60 seconds per side for rare (internal temperature ~115–120°F / 46–49°C). If your loin is thicker than 1 inch, sear each of the four narrow faces briefly (20–30 seconds) to form a crust. Avoid cooking through — tuna should be bright red/pink inside.

Rest and slice

Transfer the seared tuna to a cutting board and let rest 2 minutes. Using a very sharp knife, slice the tuna crosswise into 1/4-inch thick slices. Arrange slices slightly overlapping on a serving platter.

In a small bowl or jar combine 2 tablespoons Dijon mustard, 1 teaspoon whole grain mustard, 1.5 tablespoons honey, 1 tablespoon apple cider vinegar, 2 tablespoons mayonnaise, and 1/2 teaspoon sriracha. Whisk while slowly streaming in 2 tablespoons extra-virgin olive oil until emulsified. Season to taste with 1/4 teaspoon salt and 1/8 teaspoon black pepper. Taste and adjust sweetness or heat as desired.

Toss greens

Place 4 cups mixed greens in a bowl. Add 2–3 tablespoons of the spicy honey mustard dressing (reserve the rest for passing). Toss gently until evenly coated but not soggy.

Arrange and garnish

Place the dressed greens alongside or under the sliced tuna. Sprinkle 1/2 cup fried onion straws over the greens and a few atop the tuna for crunch. Serve with lemon wedges on the side for squeezing over the fish. If desired, drizzle a teaspoon of extra dressing over the tuna slices.