Ingredients 1/2 cup low-sodium soy sauce 1/4 cup scallions (chopped, white and light green parts) 2 tablespoons fresh lemon juice 1 teaspoon sesame oil 1 teaspoon fresh ginger (grated) 4 (6-ounce) tuna steaks 1/2 cup sesame seeds (white and black combined or white only) 1/2 teaspoon cornstarch 1) Gather the ingredients. 2) In a large zip-top bag, combine the soy sauce, chopped scallions, lemon juice, sesame oil, and fresh ginger.