Pan seared sushi grade ahi is on the top of my list lately. Local organic butcher shop keeps some in stock and it is amazing. Egg white washed and covered in sesame seeds. About 45 seconds on each side in a hot cast iron skillet.
Brother, I was in Japan for 6 yrs. 3 on the Midway, 3 more on the economy in Tokyo after I got out working with my Wife for the Labor Minister of Japan. I ended up working for one of his personal secretaries that went his own way opening a trading company with the Congressman's blessing. We used to fly Big Eye outta Hawaii and Blue Fin outta the East Coast (ME/MA) and straight to Tsukiji Market. We tried to do Yellow Fin, but it became problematic and the quality was well below acceptable by the time it hit the market due to transit time to mother ship and lack of refrigeration in the regions we were attempting. There is NOTHING in this world like FRESH high grade Big Eye or Blue Fin Tuna. If it's not gonna be Sushi or Sashimi, then the only other way I like it is quickly seared. I hate fully cooked Tuna. I still cringe at Tuna Casserole, which I don't eat, ever.