Soak moong dal in hot water for 10 to 15 min. then grind moong dal, rice flour, green chillies, ginger into fine paste till we see small bubbles in batter. Batter should be like regular dosa batter. Heat non stick dosa tawa on medium heat pour batter and spread thin as much as possible. Add little oil or ghee roast till it crispy. Serve with any chutney.