Grind some grated coconut and green chillies into a thick paste.
Add thnis to thick curd and keep it aside.
Rinse the required amount of urud dal(black gram) for about 1 1/2 hours.
Grind into a thick paste.
Add salt, coconut pieces, black whole peppers, and asafoetida.
Take a small piece of plantain leaf or plastic sheet of paper and tap the flour on the sheet into a round flat shape Make a small hole in the middle so that it gets fried uniformly.
Drop this carefuly into boiling oil and fry till it turns golden brown.
Put the vadai immediately in a vessel of water and after about 2 minutes add it to the curd mixtue.
Add fresh coriander leaves, boondi.
Splatter with mustard and asafoetida.