The above ingredients can be found in a lot of regular grocery stores. But you will find them in just about any Asian grocery store. There are imitation mirins out there, which are without alcohol they are fine but tend to be sweeter I would use less if buying these.
Cover one side of tuna completely with sesame seeds and place steaks back in fridge.
Combine all the other ingredients in a saucepan heat until blended and sugar has dissolved. Leave on low heat to keep warm.
Heat some olive oil in a fry pan, place Tuna sesame seed side down cook for 4 minutes turn over and cook on the other side for a further 4 minutes. Tuna should be pink in the middle so vary cooking time for how thick the cut is. You can cook it all the way through if preferred, but the tuna will be a lot drier and tough.
Serve tuna on plate with dipping sauce in separate small serving bowls.
I served mine with spinach topped with a roasted sesame seed dressing.
For a photo visit http://the-best-recipes.blogspot.com/.