This beautiful dish presents crisp-skinned, fresh white fish in a light and aromatic broth. It is important to use whole spices here, as their flavor is cleaner, lighter, and zingier than ground spices. The tamarind adds a delicate sourness and fresh curry leaves lend an incomparable citrusy and delicately aromatic flavor. Both tamarind and curry leaves are available from Asian food stores and some grocery stores.
Excerpted from SPRING by Skye Gyngell by arrangement with Quadrille Publishing, distributed by Chronicle Books, Copyright © 2016 by Skye Gyngell.
To make tamarind water, soak pieces of tamarind pod in hot water to cover 15 to 20 minutes, then strain. The water will have taken on the tamarind flavor.
Preheat the oven to 350 degrees F. To cook the fish, place a large nonstick ovenproof pan over high heat, and then add the butter. Season the fish generously with salt on the skin side only. When the butter is melted and sizzling, lay the fish, skin side down, in the pan and cook a couple of minutes until the skin is golden. Without turning the fish, transfer the pan to the middle shelf of the oven and cook a further 3 to 4 minutes until the fish is just cooked.
For the aromatic broth, put a large, heavy-based pan over medium heat. When hot, add the mustard, cardamom, and fennel seeds and toast gently, stirring, a minute or until they begin to jump from the base of the pan. Turn down the heat slightly and add the ghee (or butter), onions, ginger, and a little salt. Cook gently 15 minutes until the onions are soft and translucent. Add the curry leaves, sliced chilies, and tamarind water and cook 5 minutes. Now add the tomatoes and cook a further 20 minutes, stirring every now and then.
Taste the broth and adjust the seasoning—it may need a little more salt. Spoon the broth into warm bowls and lay the fish fillets on top. Scatter the curry leaves and sliced chili to taste over the dish and serve with lime wedges. I really enjoy eating this dish accompanied by steamed Asian greens or spinach and a little bowl of steamed jasmine rice.