Soak the tuvar dal for about an hour and drain well. Grind the dal, turmeric and asafetida powders, red chillies, curry leaves and salt into a paste without adding water.

Make small patties and steam cook (in an idli stand) for about 10 minutes. Or pat the paste flat onto a plate and steam cook. Cool slightly and crumble by hand. If the steam cooked batter is too hard to crumble easily( this happens sometimes if it cools down), use a grater.

String, chop the beans into small pieces and cook with a little salt till well done but firm. I prefer to do this in the microwave.

Heat oil in a pan, add mustard seeds. When they splutter, add the urad dal. When this browns, add the cooked beans. Stir a couple of times and add the crumbled dal. Mix and cook on low heat, stirring occasionally, till the dal starts becoming crisp. The Usili is ready to serve.