Take butter milk in a big vessel. If using curds, add 300-350 water and blend with hand or electric whipper till smooth. Smash ginger. Take in a muslin cloth. Dip like a pouch in the butter milk and rub the ginger in it with fingers, so that the juice mixes in the buttermilk and fiber remains in the cloth. Remove cloth. Pass 1 chilli, coriander and mint through. Heat oil in a crucible, a crusher add the seeds, 1 chilli halved, curry leaves and asafoetida. Pour into the buttermilk. Add crushed greens (the paste of chilli and coriander), salt and jeera powder. Chill before serving. An excellent post-lunch equaliser.