Thaw if needed: If your tuna is frozen, thaw it in the fridge overnight. For a quicker method, keep it sealed and submerge in cold water for 30–45 minutes. Pat very dry with paper towels.

Make the marinade: In a small bowl, whisk 2 tablespoons soy or tamari, 1 teaspoon sesame oil, 1 tablespoon olive oil, 1 teaspoon lime juice, 1 teaspoon honey, 1 minced garlic clove, and 1 teaspoon grated ginger. Add black pepper to taste.

Marinate briefly: Place tuna in a shallow dish. Spoon the marinade over both sides and let sit for 10–15 minutes at room temperature. Don’t go longer than 30 minutes or the acid may firm up the exterior too much.

Preheat the air fryer: Set it to 400°F (205°C) for at least 3 minutes. A hot basket helps create a nice crust.

Prep the steaks: Remove tuna from marinade and lightly pat the surface dry again. Brush or spray with a thin layer of oil. Sprinkle sesame seeds on both sides and press gently so they stick.

Arrange in basket: Place the steaks in a single layer in the air fryer basket. Leave a little space between pieces for airflow. If your basket is small, cook in batches.

Cook time: Air fry at 400°F (205°C) for 3–5 minutes total, flipping once halfway. For 1–1.25-inch steaks, start checking at the 3-minute mark. Aim for a deep sear outside and medium-rare center.

Check doneness: Tuna should feel springy but not firm. If you prefer more doneness, add 30–60 seconds. Use an instant-read thermometer if you like: about 95–100°F for rare, 110–115°F for medium-rare, and 120–125°F for medium.

Rest briefly: Let the tuna rest for 2 minutes. This helps the juices settle without overcooking.

Slice and serve: Slice against the grain into thick strips. Finish with a squeeze of lime, a pinch of salt if needed, and garnish with green onions and extra sesame seeds. Serve over rice or greens with cucumber and avocado.