Prepare the Dal: Soak the chana dal in water for at least 3 hours. After soaking, wash it well and drain all the water.
Make the Batter: In a grinder, combine the soaked chana dal, green chillies, ginger, garlic, cumin seeds, and carom seeds. Grind to a coarse paste.
Combine Ingredients: In a large bowl, mix the ground paste with sesame seeds, coriander powder, turmeric powder, asafoetida, red chilli powder, and salt.
Add Veggies & Flours: Add the chopped coriander leaves and grated potato to the bowl. Mix well, then add the rice flour and gram flour. Combine everything to form a dough-like mixture.
Steam the Vadi: Grease a steamer plate with oil. Take small portions of the mixture and shape them into thick, round patties. Place them on the steamer plate and steam for 15 minutes.
Cool and Cut: After steaming, let the vadis cool down for a few minutes. Then, cut them into your desired shapes.
Fry to Perfection: Heat oil in a pan for shallow frying. Carefully place the cut vadis in the hot oil and fry on medium heat until they are golden brown and crispy on both sides.
Serve Hot: Your Crispy Vadi is now ready! Serve it hot with your favourite chutney or sauce.