Natasha - do you mean the one near the church? That's Ban Song Thai. Also good but pricey.

I had yummy cocktails here:
Restaurant Schmuklerski
Badenerstrasse 101
8004 Zürich/ZH
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).