Sauce: heat the oil. Sauté the onions and garlic. Add the tomatoes. Simmer gently over medium heat, stirring throughout, for 5 min.
Add the remaining ingredients to the tomatoes form, cover with a lid and simmer on low heat for 5 min. Season the sauce with salt and freshly ground pepper to taste.
Heat the butter. Lightly fry the giant prawns. Add to the hot sauce and simmer for 3-4 minutes.
Arrange on warmed plates. Sprinkle with the chopped coriander.
* from the delicatessen dept. Grocery store