Grind the deskinned avarekalu, ginger, green chillies and cumin seeds into a little coarse paste with any water. Sprinkle a little water only if needed.
Add salt, hing, chopped onion and coriander leaves to the ground beans and mix everything together well.
Divide the batter into 15 round balls and flatten them to make a vada shape.
Slowly drop them in hot oil and deep fry them till they are golden brown on both sides.
Drain on paper towels and serve hot with tea or coffee.
Video
Notes
Use more green chillies if you want more spiciness.