Finely slice the onions (about 1 mm thick) and separate the layers by hand.
Add lemon juice and salt, mix well, and let rest for 10–15 minutes to release moisture.
Add the spices, chopped coriander, green chili, and rice flour.
Gradually add chickpea flour, mixing by hand. Add a little water only if needed, when the onion strands start sticking together, it’s ready.
Put the oil in a deep pan or wok on high heat.
Once the oil is hot, take small portions of the mixture, press slightly with your thumb, and drop gently into the oil.
Fry them for 4-5 minutes on medium heat.
Flip them, turn the heat on high, and fry until golden brown and crisp.
Drain on paper towels and serve hot.
Onion Bhajis are best enjoyed with Green Chutney (made with coriander and mint) or a cooling Yogurt Raita. And if you want the full Indian experience, serve them with a hot cup of Masala Chai.