Soak the dal in water for 3 hours and then drain
In a food processor combine three tablespoons of the soaked dal with salt and grind to a thick purée.
Add the remaining soaked dal and grind coarsely. Since the dal absorbs water during soaking, there is no need to add extra water when grinding . Mix in the chickpea flour to give a very thick paste that can be shaped into small discs.
Tip into a mixing bowl, sprinkle chopped chillies, onion, grated ginger, and curry leaves and mix well.
Heat the oil in a heavy bottomed wok or deep frying pan. When the oil is hot, wet the palms of your hand and shape about a tablespoon of the dal mixture into a 1 1/2 to 2 inch round disc.
Slide the vada gently into the hot oil. Repeat with the remaining mix. Fry vadas for approximately 3 to 5 minutes till they turn golden brown and crisp. Drain on kitchen paper and serve.
