Peel the sharp edges alone of the ridge gourd as shown in the picture (refer above). Let some of the green skin be there in the vegetable.
Chop them in to chunks and pressure cook it with just little water sprinkled, say one or two tablespoons.
Cool down and grind it into a smooth paste.
Extract tamarind juice and chop the onions into chunks. Slit the green chillies.
Heat a heavy bottomed pan with oil and season with the items given in the To temper table, in order.
Add the onion and green chilli, asafetida and fry till onions turn just transparent.
After that, add tamarind extract and boil for 2 minutes.
Finally pour the ground ridge gourd, salt to it and adjust the water consistency if it's too thick.
Boil for a 2 minutes and that's all, your gravy is ready!