Grilled Tuna Rolls

Name: Grilled Tuna Rolls
Ingredients: 2 tablespoons sweet white miso paste; 1 tablespoon vegetable, sunflower, or rice bran oil; 1 tablespoon light agave nectar; 1 teaspoon water; 1 tablespoon rice wine vinegar; Pinch of fine salt; Two ½-inch-thick tuna steaks or 1 large tuna steak, cut in half horizontally; 2 tablespoons sesame seeds, divided; 4 hot dog buns; 1 head butter lettuce, leaves separated; ¼ cup Shallot & Cilantro Vinaigrette, for serving; 2 tablespoons fresh cilantro leaves, for serving