On the morning before taking the ferry from Kadikoy to the airport, I made a dedicated hunt to find baklava. Luckily this slightly obscure place located semi-behind another cafe was found and the pistachio everything came into view.
I ordered a few different things, all variations on a theme - the dark green roll with a shiny covering, the soft green middle with pastry sides and the logroll pastry cylinder with nuts in the middle. I think my favourite was either of the first two as they had the most pistachio and syrup taste to really make the treat worthwhile. The finer nuts make a nicer texture than the harder full ones in the cylinder.
They aren't expensive. Try them all!