Prepare the Marinade: In a small mixing bowl, combine the low-sodium soy sauce, sesame oil, grated ginger, minced garlic, and a pinch of salt and pepper. Stir well to create a cohesive marinade.
Marinate the Tuna: Place the Ahi tuna steaks in a shallow dish. Pour the prepared marinade over the steaks, ensuring they are evenly coated. Allow the tuna to marinate for 15-20 minutes, turning the steaks halfway through for even flavor absorption.
Prepare the Sesame Mixture: On a flat plate, mix together the black and white sesame seeds. After the tuna has marinated, lift the steaks from the dish, allowing any excess marinade to drip off.
Crust the Tuna: Firmly press each side of the tuna steaks into the sesame seed mixture, coating them thoroughly and ensuring an even crust forms.
Cook the Tuna: Heat the olive oil in a non-stick skillet over medium-high heat. Once the oil is hot and shimmering, carefully add the sesame-crusted tuna steaks. Sear each side for about 1-2 minutes for a rare finish, adjusting the time as needed if you prefer a more cooked interior. Take care not to overcook, as this may lead to a tough texture.
Rest and Slice: After cooking to your desired doneness, transfer the tuna steaks to a cutting board and let them rest for about a minute. Then, using a sharp knife, slice the tuna against the grain into 1/2 inch thick pieces for tender servings.
Plate and Garnish: Arrange the beautifully sliced tuna on a serving plate, artfully sprinkling the finely sliced green onions over the top for a pop of color and flavor.
Notes
Serve with wasabi and pickled ginger for an enhanced experience.