Soak 1/3 cup moong dal for 2 hours; Then drain the water and blend it in a mixer nicely.
In a pan, temper 1/2 tsp mustard, 1/2 tsp urad dal, 1/2 tsp channa dal, 1 spring curry leaves, hing, 1 inch chopped ginger. Cook until all the dal is roasted nicely.
Add 2 tbsp grated carrots and saute it for 1 min.
In a bowl, mix blended moong dal, 3 tbsp curd and carrot mix.
Add 1 tsp chopped coriander, hing, salt and mix it well.
While you are about to cook, add 1/2 tsp Eno salt and mix it well
The idly batter is now ready.
Grease the idly plate with oil, pour the batter and cook for 15 mins in medium flame.
It is done. Serve it hot with any chutney.