Aromas of lemongrass, kaffir lime leaves and galangal waft through the dining arena where this lightly sweet, spicy, brothy treasure is served. On my last journey to the small city of Lumnaria in the Lopburi province of Thailand, the family of one of my former students, Fah Vorarittinapap, showed me how rural Thais add a natural layer of sourness with chopped young tamarind leaves. Alas, we don’t grow tamarind in the West, so we use fresh lime juice.

If you can’t find head-on shrimp, use stock (seafood or chicken) instead of water for this broth. Whenever you cook shrimp, collect the shells in your freezer. They can be used to enrich stock for soups like this. Just simmer them with the stock for thirty minutes, and then strain. The nuance of flavor they add can make all the difference.