Crumble the leftover Idli and keep aside.
Finely chop the onion, green chillies, coriander leaves and curry leaves.
Heat a pan, add coconut oil, chana dal (bengal gram dal), urad dal, whole red chillies and mustard seeds. Once mustard crackles, add hing or asafoetida.
Now add the finely chopped onions, green chillies and curry leaves. Saute well until the onions are translucent.
To this, add the crumbled idli, salt to taste, sugar, red chilli powder and finely chopped coriander leaves. Mix well. Note - Idli contains salt so add with caution.
Serve this hot with any chutney and a cup of tea for breakfast or snack.