This is my husband's all time favorite Thai soup - but up until now, I haven't been able to recreate it at home. I've played around with several versions to come up with this one. The authentic ingredients make a HUGE difference - although you can use substitutions, of course, it does affect the outcome. I have been able to find the galangal root (much preferred over ginger!!), the lemongrass, and the kaffir lime leaves at my local asian market. Yum yum yum, worth the extra shopping trip!