Zagreb is not a metropolitan city like other much bigger European cities but we sure welcome any new cuisine, so is Thai - Umami grill where genuine Thai personnel is preparing food, where space is small but always packed and food is always yummy. The steady menu list is concise fulfilled with different daily specialties - specially soup.
When in Zagreb, Croatia in general, I always recommend to try local food, but hey I know personally when away on a trip, one can miss his/her favorite food, most certainly that being Thai. For genuine taste and really affordable prices, Umami grill is more than reasonable choice.
Pad Thai is superb, and any soup you choose is excellent choice, just be careful of the very hot ones! :)
Su-Sa: 10:00-23:00