Fry onion in coconut oil and add the ground paste to it and fry again.
Add the chopped prawns and curry leaves and mix all the ingredients well.
Keep the masala aside.
Mix all the ingredients for the ada to make a thick paste.(see not to add water too much)
Press the thick paste to a medium thickness in a banana leaf.
Spread the prawn masala on top of the ada.
In another banana leaf press the paste again in same thickness and size as before.
Place this ada carefully above the spread masala.
Repeat the process again making 2 layers of masala.
Fill a steam vessel with half of water and place the stand above it.when the water boils place the ada along with the banana leaf on the stand and cover the vessel with a lid.