Mix together the ingredients for marinating and marinate the prawns in it for half an hour.
Shallow fry these prawns in oil, but do not wait too long as it will make the prawns rubbery.
Next, saute the onions in the oil used for frying prawns. Fry till the colour of onion changes.
Add the ginger garlic paste and saute again till the fresh smell of the paste goes away.
Add the powders and fry well.
Add black pepper and salt.
Add tomato and saute well.
Finally, add the coconut milk.
When it boils, reduce the flame.
Add the fried prawns and let it simmer for 3 minutes.