Crumble the idlis coarsely with your fingers or you can use the mixie for better results. Cut the idlis into 2-3 pieces and put it in the mixie and pulse it for a few seconds. The idlis will get crumbled evenly. Keep it aside.
When dal turns golden brown, add finely chopped onions, green chillies, ginger, turmeric powder, salt needed and saute till onions turns transparent. Then add the crumbled idli and mix well.