How to Grill Tuna Steak. We all have evenings when we just can't decide what to cook for dinner. The next time you're in this situation, grill tuna steaks. This is a fast, easy and inexpensive dinner that your entire family will enjoy.

Make a marinade by combining 1/2 cup of olive oil, the juice of one lemon, 2 tbsp. fresh oregano, 1/4 tsp. salt and a dash of pepper.

Place the tuna steaks in a casserole dish.

Pour the marinade over the tuna steaks and cover. Marinade the tuna in the refrigerator for up to three hours.

Preheat the grill.

Grill the tuna for 4 minutes on each side.

Eat promptly and enjoy!