Natasha - do you mean the one near the church? That's Ban Song Thai. Also good but pricey.
I had yummy cocktails here:
044 241 1541
It's next to Plaza cinema, corner of Langstrasse/Ankerstrasse and Badenerstrasse and just a short walk from Ah Hua
They also do a good new york cheesecake (not sure if it's the best in Zurich, but I really liked the atmosphere and good cocktails).