To begin with, combine the green moong dal, yellow moong dal and urad dal in a deep bowl with enough hot water. Cover with a lid and keep aside for 1 hour. Drain well. Combine the soaked and drained dals along with ¾ cup of water in a mixer and blend till smooth.
Transfer the mixture into a deep bowl, add all the other ingredients and mix well.
Heat a non-stick tava. Pour a ladleful of the batter on it and spread it evenly to make a thin circle.
Cook, using ¼ tsp of oil, till it turns golden brown in colour from both the sides. Flip it once done.
Serve the mixed dal chillas immediately with chutney.