Drizzle both sides of the tuna steaks with oil, then squeeze half of the lemon’s juice on top. Rub the garlic, basil, salt, and pepper on both sides of the steaks, seasoning to your taste.
Grill, covered, or broil for 4-5 minutes on each side or until done to your preference. (I like a little bit of pink in the center so it doesn’t get too dried out.)
Serve with the other half of the fresh lemon.
Notes
If broiling, fill the bottom of the broil pan with a little bit of water. It keeps the meat from losing too many juices and makes cleanup easier.