Soak the red beans (red chori) for minimum 45 minutes and drain it.
Grind the soaked beans with green chilies, ginger piece and cumin seeds. Do not add water while grinding. The final batter should be coarse in texture.
Remove the batter in a mixing bowl and mix in the chopped onions, chopped curry leaves, asafetida and salt.
Heat the oil in a kadai or wok.
Take a small portion of the vada mixture; make a ball and press between your palms to form a small patty.
Deep fry in oil for about a minute on each side till it turns brown and crispy.
Remove the vadai and drain the excess oil using a paper towel.