Soak 100g urud dal for 1 hour. Add 3 green chillies, 1/4 tsp salt, a pinch of asafoetida and grind it into a thick coarse paste. Place this on idli plates and steam. Remove and when it cools a little separate them gently.  Heat 4 tsp of oil in a fry pan, add mustard seeds. When it pops, add 6 tsp of grated coconut, cooked urud dal mix. Add a bunch of curry leaves.  Using this as stuffing, make kozhukkattais as described in kozhukkattai.