PRAWN VINDALOO

1 kg fresh prawns shelled and de-veined
2 medium sized onions chopped
2 teaspoons chilly powder
2 teaspoons cumin powder
2 teaspoons ginger garlic paste
2 tablespoons vinegar
Salt to taste
1 sprig curry leaves (optional)
2 tomatoes pureed
3 tablespoons oil

Wash the prawns well and keep aside. Heat oil in a pan and add the curry leaves and onions and fry till light brown. Add the ginger garlic paste and sauté for a while. Add the chilly powder, cumin powder, pepper powder, tomato puree and salt and fry for some time. Add the prawns and the vinegar and mix well. Add a little more water and cook till the gravy is slightly thick and the prawns are cooked