Pound together the ginger, garlic and chilli with a pinch of salt.
Marinate the prawns with salt, chilli powder, cumin, ginger-garlic-green chilli paste, lemon juice and curry leaves. Set aside for 20 minutes.
Heat oil in a fry pan and have it ready to go. Add the besan (chickpea flour) to the prawns mix through until each prawn is evenly coated. You want a light thin coat.
Sprinkle on the coarse rice flour to get a even crust over the prawns. Make sure your oil is hot (atleast 170-180°C) before you add the prawns. Deep fry (for best results) for about a minute (adjust based on the size of the prawn).
Serve hot with some crispy whole curry leaves and coriander mint chutney