Cut the vegetables into thin sticks. Mix together the besan flour, chilli powder, turmeric, asafoetida and a pinch of salt. Add enough water to make a thick batter that will hold the vegetables together. Mix the vegetables and curry leaves into the batter.
Fill a karhai or heavy-based saucepan one-third full with oil and heat to 180°C/350°F (a cube of bread will brown in 15 seconds). Li