Step 1

In a medium bowl mix together the oranges, pepper, onion, mint and vinegar. Season with salt and pepper and set aside.

Step 2

Heat the grill to high-heat. Oil the grates generously with vegetable oil (not cooking spray), and let heat up. Rub each tuna steak with a little bit of olive oil, and then sprinkle with coriander, salt and pepper. Place the tuna steaks on the grill and cook 4 to 6 minutes, turning just once. It will still be pink in the center.

Step 3

Top with salsa, and serve.