Assamese Khar — Alkaline Banana Ash Cooking (কাৰ)

Assam; khar cooking is documented as a uniquely Assamese technique; the Brahmaputra valley's abundance of banana plants made ash lye a natural, readily available cooking medium

Khar (কাৰ) is one of the most unusual cooking mediums in Indian cuisine: a strongly alkaline liquid made by filtering water through the ash of banana plant (Musa paradisiaca) stems or peels, resulting in a potassium hydroxide-rich solution that is used to cook fish, gourd, and lentils in a technique unique to Assam. The alkalinity softens fibrous plant material dramatically (the same principle as using lye in Nordic lutefisk or Japanese ramen's alkaline noodles), imparts a distinctive mineral, slightly soapy-savoury flavour note, and acts as a preservative. The dish 'khar' is also the name of the ingredient and the dish — khar fish (কাৰ মাছ) is a whole prawn or small fish cooked in the alkaline solution with raw papaya.

Khar dish (typically raw papaya or prawn) served as the first course of a traditional Assamese meal — the alkaline note is meant to stimulate digestive enzymes and prepare the palate. Eaten with rice.