Light Grill: Place Cowboy Charcoal Hardwood Briquets in a charcoal chimney. Add a fire starter below the chimney and light the coals. Once the coals ash over, dump them into the grill. Adjust the vents, so the grill reaches a temperature of 400F degrees.
Make Sauce: While the grill is heating up, combine the dipping sauce ingredients in a small bowl and set aside.
Season: Remove the tuna steaks from their packaging. Pat them dry. Rub with oil and season with salt and pepper.
Oil Grill: Brush some oil on the grill grates to prevent the tuna from sticking.
Grill: Place the steaks on the grill over direct heat. Grill for 2 minutes. Don’t move the tuna steak while it’s cooking. It will sear and should easily flip when ready. Flip and grill for another 1-2 minutes. The tuna should still be red in the center.
Slice: Remove from the grill. Slice into strips. Garnish with sliced green onions and sesame seeds. Serve with the dipping sauce.
Notes
If you're using a gas grill, turn the burners to high. For a pellet grill, set the temperature to 425F degrees. This can also be cooked using a grill pan or skillet.