I feel a bit ashamed to call this a recipe, but I thought up the sauce and it seems to be popular with everyone who has eaten it, so I guess it deserves a mention here! I didn’t have a ripe avocado to hand, but I advise you to cut one thinly and use in between the tuna slices for a much nicer presented dish than my own.
When you buy the fish, if it isn’t marked ‘sashimi’, make sure you ask the fishmonger if it can be eaten as such – simply having raw fish is not good enough for this delicate dish. For the sauce, I didn’t write any quantities as it’s all down to taste, so have fun dipping your finger in midway through and seeing what you like
Chop the chives. Mix all the sauce elements together. You’re done!