I love ahi tuna. I love it grilled, raw and just about every way in between. I finally perfected seared tuna. The key is to marinate the tuna and then pat the outside to nearly dry with a paper towel before searing.
1/2 tbs sesame oil
1 tbs soy sauce
1tsp rice wine vinegar
1 tsp garlic powder or smashed and chopped fine
1 tsp ginger powder or smashed and chopped fine (or you can skip everything from the sesame oil through the garlic powder and just use gyoza sauce, that’s what we do)
1 tbs sesame oil (or peanut or vegetable)
1tps Sriracha sauce
1 tbs toasted sesame seeds per tuna steak
Combine the first five ingredients by whisking them together in a small bowl. Pour 1/2 to 2/3 over the tuna steaks and let marinate at least an hour. Reserve remainder for dipping sauce. Heat pan over medium high heat. Add oil and Sriracha sauce. Sear steaks each side (including ends!) until pink about 1-2 minutes per side. If you prefer your tuna less raw in the middle cook each side a bit longer. Remove from heat. Sprinkle with sesame seeds. (You’re really kind of coating it with the sesame seeds.)
I love this dish. I crave it regularly. It’s super simple to prepare and as long as you remember to cut with the grain, looks good on a plate. (I often forget.) The spice can be tempered to your taste by adding more or less Sriracha.