Step 1: Prepare the Marinade

• In a small bowl, whisk together soy sauce, sesame oil, lime juice, minced garlic, and grated ginger. This combination adds depth and a hint of sweetness to the fish.

Step 2: Marinate the Tuna

• Place the tuna steaks in the marinade, ensuring they’re evenly coated. Let them rest in the refrigerator for 10–15 minutes to absorb the flavors. Avoid marinating for too long, as the acidity in the lime juice can start to "cook" the fish.

Step 3: Coat with Sesame Seeds

• Remove the tuna steaks from the marinade and pat them dry. Press sesame seeds onto all sides of the steaks to create a crunchy, flavorful crust.

Step 4: Heat the Pan

• Heat a heavy skillet, such as cast iron, over medium-high heat. Add a drizzle of sesame oil or a neutral oil like canola to the pan and allow it to heat until shimmering.

Step 5: Sear the Tuna

• Place the tuna steaks in the hot pan and sear for about 1–2 minutes per side. For a rare finish, the interior should remain pink. Adjust the searing time to your desired level of doneness.

Step 6: Rest and Slice

• Remove the tuna from the pan and let it rest for 1–2 minutes. This allows the juices to redistribute. Slice the tuna thinly against the grain for the best texture.