Water Spinach

Along with curry leaves, this is the ingredient that makes Sri Lankan food distinctly Sri Lankan. As the name suggests, it comes from the nearby Maldivian islands, usually bonito or skipjack tuna, that is dried and smoked until it becomes very hard, almost like wood. It is usually sold in chips or flakes and can be found in Sri Lankan and some Indian grocers. The flavour is strong but not nearly as stinky as some other Asian dried shrimp pastes or fish sauces. (I grew up thinking it was called ‘mouldy fish’ which was always a little disconcerting.) It is either pounded until fine and mixed into sambols or the flakes are added to curries and vegetable dishes. It works as a thickener, an added source of protein and as a way to balance flavour, much like you would with fish sauce. Use it subtly to add a salty and smoky umami note, or more liberally as a flavour in its own right. You can substitute with Katsuobushi or dried anchovies (at a stretch).