Mix flour, water, oil and salt, knead to dough. Keep aside.
Heat oil in a pan, add cuminseeds, chillies, onion saute well. Add moong, chilli powder, salt and saute till moong is slightly cooked. Once it is little soft, add coriander leaves and salt.
When cold, grind the mixture coarsely. Squeeze juice and mix well.
Make balls from the dough and stuff the above mixture and close, roll with a pin. Cook on tava adding oil.