Gaeng Som Pla Gapohng Daeng (Southern Thai Red Snapper and Green Papaya Sour Curry)

Generally speaking, there are two styles of gaeng som, a spicy and sour water-based Thai curry that typically features seafood of some kind. One is from the southern part of Thailand and one is from the country's central plains; this recipe is for the Southern-style gaeng som, which is referred to as gaeng leung or gaeng som phak dtai outside of the south. While both versions share a spicy-sour flavor profile, use water or stock instead of coconut milk, and typically incorporate a combination of seafood and vegetables, they each use ingredients that are readily available in their respective regions.

Regional Styles of Gaeng Som

In the South, the curry paste that forms the base of the curry is made from fruitier and much spicier chiles that come in a range of colors, like prik khee nuu suaan, prik deuuay gai, and prik gariiang, and consequently the curry has a lighter, brighter color. You'll commonly find saltwater fish like mackerel (pla thuu) or brackish water fish such as mullet (pla grabaawk) or barramundi (pla gapohng) added to the curry in the South, although you'll also sometimes see it made with shrimp or even pork. You'll find all kinds of vegetables and fruit added to the curry, too, including pineapple, pickled bamboo, elephant ear stalks, hearts of palm, and lotus stems, and lime juice, tamarind, or asam fruit are commonly used as souring agents.

The central plains version of the curry is a little sweeter, due to the inclusion of palm sugar in the curry paste, and slightly less spicy because it uses different chiles; it's also a relatively simple curry paste, and can consist of just spur chiles (prik cheefa), shallots, and shrimp paste, although sometimes grachai (also known as fingerroot or wild ginger) is added for its distinctly piney aroma (it's also considered a cooling spice that blunts any fishy odors), and sometimes the paste is pounded with a little boiled fish to give it a thicker texture. Fresh water fish such as snakehead fish is usually added to the curry along with vegetables like cabbage, Napa cabbage, long beans, okra, Thai morning glory (water spinach), and more.

Gaeng Som Ingredients

For this recipe, I use a paste made from dried and fresh chiles, turmeric, shallots, garlic, and fermented shrimp paste, which I boil in water or stock and then season with fish sauce and tamarind, to add a subdued sourness. I then use this flavorful liquid to simmer pieces of green papaya and red snapper (pla gra), which take on a beautiful yellow hue from the turmeric. Right before serving, I add some freshly squeezed lime juice for a fresh and bright note of acidity.

I call for using chiles that are known in the US as “Thai chiles,” although I prefer to call this variety by its Thai name, prik jinda, since there are so many Thai chile varieties. The dried chiles produce a lingering heat at the back of the throat while the fresh chiles provide a sharp, front-of-the-mouth burn.

Prik jinda can easily be found in Southeast Asian markets. Fresh turmeric is increasingly available in stores like Whole Foods, but I find it best to go to South Asian markets. Trying to find fresh turmeric and prik jinda is important even if you choose to use store-bought curry paste, as this curry's flavor really relies on fresh ingredients. If you choose to use store-bought paste, make sure to look for one that is labeled gaeng leung, or sour yellow curry, and avoid using gaeng garee (karee, gari), known as yellow curry in English, which has a different flavor profile.

Methods for Making Gaeng Som Paste

The curry paste can be pounded in a mortar and pestle or blended; if you choose to blend it, you'll need to add one cup of water to help break down the fibrous aromatics into a smooth paste. While blending will produce a more puréed paste with less textural nuance than a pounded paste, it's a completely acceptable quick method to make curry pastes for water-based curries. (A word of warning: The turmeric in the paste may stain your blender jar.)

This curry is best paired with side dishes that can counter its sour and spicy flavor profile, like galam plee pad nam pla (stir-fried cabbage with fish sauce and garlic) or a Thai omelette. And, as always, serve the curry and sides with jasmine rice.