Clean and wash prawns well, marinate with turmeric, red chilli powder, salt. Keep aside.
Grind coconut into smooth paste by adding half a cup of water and set aside.
Heat oil in a pan, add chopped onions and green chillies. Fry until the onion turns brown.
Add ginger garlic paste and sauté for 2 minutes.
Add marinated prawns and cook till the water evaporates.
Now add coconut paste and cook till you get gravy consistency.
Add salt as per taste.
Add garam masala and mix well.
Garnish with coriander leaves and serve hot with steamed rice.