If using dried seaweed, place the seaweed in a small bowl, add enough cold water to cover. Set aside to soften for 15 minutes. Drain and coarsely chop the seaweed before using.
Prepare the grill for direct cooking over high heat (.
In a medium bowl mix the onion, scallion, soy sauce, sesame oil, ginger, and chile. Add the seaweed.
Related Grill Skills
Chopping an Onion
Mincing Ginger
Brush the tuna with oil and lightly season with salt and pepper, patting the seasoning into the fish. Brush the cooking grates clean. Grill the tuna over direct high heat, with the grill lid open, just until seared on both sides but still rare inside, about 2 minutes, turning once.
Brush the tuna with oil and lightly season with salt and pepper, patting the seasoning into the fish. Brush the cooking grates clean. Grill the tuna over high heat, with the grill lid open, just until seared on both sides but still rare inside, about 2 minutes, turning once.
Transfer the tuna to a cutting board and cut into 12- to 18-millimeter cubes. Add to the bowl containing the onion mixture and toss to combine. Divide equally into individual bowls. Sprinkle with the sesame seeds. Serve warm with lemon wedges, if desired.