Wash rice and quinoa thoroughly and combine them. Add 4 cups of water and soak them for at least 6 hours.
Wash Urad Dal and soak it in 2 cups of water for at least 4 hours.
Grind the soaked grains and lentils till you get a smooth batter. Add water, if needed to get a flowing batter ( not too thin though).
Whisk the batter for a few minutes. Then cover and let it ferment overnight in a warm place.
The next day, add salt and mix the batter. Add a little bit of water, if the batter looks too thick. For perfect idlis, the batter should neither be too thick nor too thin.
Heat water in the idli steamer. Grease the idli plates and pour the batter into each section.
When the water in the steamer starts bubbling, place the idli plates in the steamer.
Steam for 15 minutes. Then remove from heat. Let it stay covered for 5 minutes before you open it.
Remove the trays and let them rest on the kitchen counter for 2 minutes.
Sprinkle some water on each plate. It will ease removing idlis.
Remove the idlis and serve them hot with your favourite chutney. You can add some ghee to the idlis to further enhance the taste.