Heat oil in a pan
Temper mustard in it and allow it to splutter
Add urad dhal, chana dhal, curry leaves and fry well
Add turmeric powder, snake gourd little by little, salt and mix well
Close the lid and allow it to cook till tender, sprinkle very little water if required
Add red chili powder
Add besan flour little by little and mix well, few lumps will be formed due to heat, don't worry it can be rectified
Once besan is fully mixed sprinkle little more water and mix well now the lumps will break and bind together
If you wish to roast the curry, add little more oil, simmer the flame and allow it for 3~5min
Serve hot with any rice item