Place the chickpea flour, rice flour, green chilies, cumin powder, Kashmiri chili powder, turmeric powder, grated fresh ginger, fresh cilantro leaves, salt, and asafoetida powder into a mixing bowl.
Whisk them together.
Add the very thinly sliced onions and squeeze them by hand as you mix them with the other ingredients so that their moisture creates a thick dough around the sliced onions.
Add the water and mix by hand, so the water loosens the dough to coat all the onions.
Heat oil in a pot on the stove over high heat to 350-365 degrees Fahrenheit (176-185 centigrade), or prepare your air fryer, by lightly spraying the tray with cooking oil.
Form the onion mixture into roughly shaped 2-3 tablespoon-size fritters. Do not compress them or smooth the outsides, as the rough form, and stray bits of onion help the bhaji to be crispy.
Fry or air-fry in batches, ensuring not to overcrowd your pot or air fryer. Use a spider or slotted spoon to stir and flip the bhaji over as they cook once or twice. Fry for 2-3 minutes until crispy and golden brown. Too light in appearance, and they will probably not be cooked internally, and too dark and they will have a burnt taste.
Place the fried bhaji on paper towels to absorb any excess oil.
Serve with chutney, tamarind, or mint sauce and garnish with fresh mint and cilantro leaves if desired.