Gaeng som

Gaeng som is a Thai curry with a sour, hot broth, built on a red curry paste sharpened with tamarind. It is a thin, brothy curry rather than a rich coconut-milk dish.

What it really is

Gaeng som is made by pounding dried red chillies, shallots, garlic, galangal, lemongrass and shrimp paste into a paste, then simmering it in water with tamarind pulp and fish sauce. Its sourness comes from the tamarind; coconut milk is not used. The classic version is built around a fish or seafood, and vegetables such as morning glory, pumpkin or green beans are added near the end of cooking.

It is often confused with gaeng leung, which is a related sour curry with turmeric, and with tom yum, which is a clear soup with lemongrass and lime. Gaeng som is thicker and more sour than tom yum, and it is distinguished from gaeng leung by its red paste and absence of turmeric.

How it's served

• Served hot in a bowl alongside steamed jasmine rice, which is eaten with the curry spooned over it.
• Usually shared as one of several dishes at a family meal, rather than eaten as a single plate.
• Eaten with a spoon, with the rice taken in small mouthfuls and the broth sipped between them.
• Often accompanied by a plate of raw vegetables or fried fish as a contrast to the sourness.

How to write it on the menu

• Name the sourness and the fish on the menu, for example "sour red curry with tamarind and fish", so guests know it is not a coconut curry.
• State the allergens that apply: fish sauce and shrimp paste mean FISH and CRUSTACEANS, and shrimp or prawn versions also carry CRUSTACEANS.
• Give the protein choice, such as fish, prawn or chicken, and whether the vegetables are morning glory or pumpkin.
• Note the heat level, because the red chillies in the paste make the dish spicy as well as sour.