This lovely roasted whole fish is great for entertaining because the presentation is striking. The sauce uses an unusual herb called culantro in English and "pak chi farang" in Thai. It has long, tapered, saw-toothed leaves that taste similar to coriander. If unable to find, use coriander as a substitute. This recipe also calls for pla chorn, aka serpent head fish, a freshwater fish found only in SE Asia, you can substitute trout, barramundi or even tilapia.