Thanks to the person who recommended 'le Sputnik' here in Tokyo. I read it on Thursday night and was able to book a table for lunch on Friday. It was sensational, and at 6000 yen the very best value meal I think I've ever had.
This is 2* cooking and the meal was infintely more exciting than the 3* and 5 times more expensive meal I had at l'Osier on Wednesday (although TBF that was for dinner).
Can't recommend it highly enough.