Heat oil in a pan and add the onion slices and paste. Fry until the onions turn golden. Add the shrimps and continue frying. Add ginger, garlic and cumin pastes. Sprinkle salt and turmeric powder and mix well.
Now add the chopped gourds and continue stirring and mixing. Put the lid on with low heat for 10-15 minutes.
When half cooked, add the green chillies, and cover the pan with the lid again for another 10-15 minutes.
No need to add any water because the gourd will release plenty of it.