I've had this recipe and its awesome. Tuna steaks are best cooked a medium rare. Anything more takes away from the flavor of the fish. Don't worry - you won't get sick by eating it cooked that way. The worst thing you can do to a good piece of fish is to cook it to the consistency of shoe leather.
This particular recipe serves 4.

Sesame Seared Tuna

INGREDIENTS

1/4 cup soy sauce
1 tablespoon mirin (Japanese sweet wine)
1 tablespoon honey
2 tablespoons sesame oil
1 tablespoon rice wine vinegar
4 (6 ounce) tuna steaks
1/2 cup sesame seeds
wasabi paste
1 tablespoon olive oil

DIRECTIONS

In a small bowl, stir together the soy sauce, mirin, honey and sesame oil. Divide into two equal parts. Stir the rice vinegar into one part and set aside as a dipping sauce.

Spread the sesame seeds out on a plate. Coat the tuna steaks with the remaining soy sauce mixture, then press into the sesame seeds to coat.

Heat olive oil in a cast iron skillet over high heat until very hot. Place steaks in the pan, and sear for about 30 seconds on each side. Serve with the dipping sauce and wasabi paste.

Let me know how you like it!! Also let me know when you're cooking it and what time I should be there. This is one of my favorites!!