Prep: 5 mins
| Cook: 10 mins
| Extra time: 30 mins
1.
In a large resealable freezer bag, combine the teriyaki sauce, oil, garlic and pepper. Place the tuna in the bag. Seal the bag with as little air in it as possible. Give the bag a good shake to coat the tuna fillets. Marinate for 30 minutes in the fridge.
2.
Meanwhile, preheat the barbecue for high heat and lightly oil the cooking grate.
3.
Remove tuna from marinade, and place on barbecue. Cook to desired doneness.