Clear, creamy, prawn, chicken, mushroom and vegetarian versions of Thailand’s famous hot-and-sour soup.
Nam sai is clear; nam khon is creamy, often enriched with evaporated milk or chile paste depending on the style.
Lemongrass, galangal and makrut lime are there to perfume the broth. Many diners leave the tougher pieces in the bowl.
Long boiling dulls fresh lime. Finish sourness near the end.