Gaeng Som — Southern Sour Curry (No Coconut) / แกงส้ม

Southern Thai — deeply regional; nearly absent from Central Thai home cooking; associated with the Gulf of Thailand coast and its abundant fresh fish

Gaeng som is the defining curry of Southern Thailand — sour, fiery, and turmeric-gold, with absolutely no coconut milk. The broth base is tamarind water (or green mango pulp, or fresh sour fruit depending on season and region) seasoned aggressively with fish sauce and the deep-fermented kapi that characterises the South. White fish (typically snapper, grouper, or the more traditional platu — short mackerel) is the standard protein. The technique is simple compared to coconut curries — paste is fried briefly, tamarind water added, fish added, and the whole thing simmered for 10–15 minutes. Speed is part of the ethos. The acidity is non-negotiable and should be bold rather than restrained.

Gaeng som's sourness acts as a digestive function — the acidity prepares the palate for the rich fish and cuts through any fatty notes, which is why it is often served as the first curry at a multi-dish Southern Thai meal.