Wash the eggplants and cut them into thin round slices.
In a bowl, mix gram flour, rice flour, turmeric powder, chili powder, cumin powder, and salt.
Add water gradually and whisk until a smooth batter forms. The batter should be thick enough to coat the eggplant slices.
Add baking soda and mix gently if using.
Heat oil in a deep frying pan over medium heat.
Dip each eggplant slice into the batter, making sure it is fully coated.
Carefully place the coated slices into the hot oil.
Fry until they turn golden brown and crispy on both sides.
Remove and place on paper towels to drain excess oil.
Serve hot with green chili, chopped onions, or sauce.