1. Soak the chana dal in enough water for 2 hours.
2. Drain and combine the dal with onions and coconut and blend in a mixer to a coarse paste, using 1/4 cup water.
3. Transfer in a bowl, add the green chillies, ginger paste, coriander leaves, turmeric and salt and mix well.
4. Heat the oil in a kadhai, drop a spoonful of batter in oil and deep fry till golden and crisp from all the sides.
5. Repeat the same to make more wadas.