¼ cup low-sodium soy sauce
2 tablespoons mirin (sweet Japanese rice wine)
1 tablespoon seasoned rice vinegar
1 tablespoon minced or grated fresh ginger
1 teaspoon sugar
1 tablespoon plus 1 teaspoon dark sesame oil
1½ pounds albacore steaks
Combine the soy sauce, mirin, vinegar, ginger and sugar in a bowl and whisk together well. Whisk in the sesame oil.
Place the albacore steaks in a large bowl or baking dish and toss with the marinade. Cover the bowl, or transfer the fish and marinade to a large zip-top bag and refrigerate for 1 to 2 hours, or longer.
Prepare a hot grill, or heat a heavy cast-iron or nonstick skillet over medium-high heat. Remove the fish from the marinade. Cook the steaks for 2 to 4 minutes on each side, depending on how well done you like the fish to be. Serve hot.
Serves 4 to 5