Separate the florets or chop them to 2-3 inch bite-sized pieces. Bring some water to a boil in a saucepan big enough to hold all the cauliflower florets.
Once the water has begun to boil, add the cauliflower florets and let them boil for 3 minutes only. Once the time is up, immediately pour it through a colander to drain the hot water.
And run some cold water over the cauliflowers immediately. Spread them on a towel to dry them out. Set it aside.
In a mixing bowl, mix together the rice flour, corn starch, chilli powder, salt, black salt, garam masala powder and amchur powder. Add few tablespoons of water and mix to make a runny batter. It shouldn't be too watery or too thick. Once we add the cauliflower, it'll further thin down by a bit.
Add the cauliflower to the mixing bowl and mix it to coat it. No need to be thorough. Heat enough oil in a frying pan.
Once the oil is hot, fry the cauliflowers in batches with enough room for the florets to float around. Let it cook for 4-5 minutes or until it is nice and crisp on the outside.
Serve it immediatley with a sprinkle of chat masala and lemon wedges and onion on the side!