The technique of bhuna-ing (when you combine English and Hindi, it becomes the hybrid Hinglish) is easy to re-create: it means to stew a sauce slowly over medium-low heat in order to cook the spices long enough for their essential oils to be released, making for a very complex-tasting curry. Here a puree of fried onions, tomato paste, and a few spices simmers gently for almost half an hour to yield a sweet, slightly tart base for large shrimp.