Mix together all of the ingredients for the marinade. Pour approximately 2/3 of the marinade into a bowl for dipping and set aside, if it is a little strong add a tablespoon or 2 of water or rice wine vinegar.

Pour the remaining marinade into a ziploc bag and add the tuna steaks. Squeeze out all the excess air and marinate in the fridge for 30-60 minutes.

Remove the tuna steaks from the marinade and gently roll in the sesame seeds.

Heat a heavy bottomed skillet until a drop of water dances across the pan and evaporates almost instantly.

You’ll cook the steaks in batches, so add about 1 tablespoon of sesame oil to the pan and then sear each tuna steak for about 30-60 seconds on each side. Don’t forget to sear the edges too!

Remove the seared steak to a serving plate and cover it with a tent of aluminum foil to keep it warm.

Repeat with remaining steaks, adding more sesame oil as necessary.

Just before serving, slice the tuna steaks on a gentle bias and serve with the dipping sauce.