Clean the prawns and remove the black thread. I kept the tails on some of the prawns. Slit the large prawns a little. Do not go overboard. It is actually not necessary so you can conveniently ignore this step.
Now mix the cleaned prawns, soy sauce, vinegar, schewan chutney and sugar together. Let the prawns marinate for 20 to 30 minutes.
Take a pan or a wok, add the oil. You can use vegetable oil or groundnut oil, I used the latter. Heat it on a high flame.
After the pan is hot enough hit the marinated mixture to the pan. If you love spicy food or want to add a little bit of zing to the dish, add two slit green chillies just before adding the marinated prawns.
Stir fry the prawns for 2 to 3 minutes.
If you keep them in hot pan for more minutes, the prawns will lose their softness and become very rubbery / chewy. When cooking sea food, timing is very important.
For more pictures and other recipes click http://lovecookingfood.wordpress.com/2012/10/22/prawns-stir-fry/