The drink was incredibly refreshing on a hot NYC summer evening. I tasted the slightly bitter earthiness of the Oolong, along with a subtle hint of something smoky that reminded me of whiskey. Shochu has a subtle flavor, and so my drink didn't have the overwhelming alcoholic taste that I usually expect from a cocktail. This makes the drink quite dangerous for me. I hardly even noticed that I was consuming any alcohol! It had a similar refreshing feel to the mugicha I recently tried. I also love that it wasn't sweet. In fact, the server warned me that it wasn't a 'sweet cocktail'.
This drink is typically called Oolong-Hai (I guess Ippudo made it more obvious for us Americans), and is popular at izakaya and karaoke bars in Japan.
If I'm ever able to snag a table at the immensely popular restaurant again, I will try the 'Green Tea High' to see how the Shochu changes the taste of the tea.