This recipe for Sour Orange Curry with Fresh Water Fish Vegetables (gaeng som pla) is quite popular in the dry plains area. It is a fairly simple boiled curry and is quite a change from the Thai food found in most Thai restaurants in the US and Europe. It doesn't contain coconut milk, lemongrass or lime. Coconut is actually quite common in the Central Plains along with the South, but less so in the North and North East.