Peel and devein the shrimp. Finely slice the onion.
Heat fat in pan and fry the onion and crushed garlic until soft.
Add the spices; cook about half a minute until fragrant. Stir in the salt and coconut milk; simmer, uncovered, for 10 minutes.
Add the shrimp and cook until opaque and curled, about 3 to 5 minutes.
Stir in vinegar. Serve over boiled white rice.
Harvey Day, The Complete Book of Curries, 1970
http://macheads2.net/recipes/PrawnBafat.html