- Heat oil in a large pan over medium-high heat. Splutter mustard and fenugreek seeds. Tip in onion, and sauté for 2-3 minutes or until browned. Add ginger, garlic, green chilies and curry leaves. Sauté, stirring, for 1-2 minutes.Add coconut slices, and fry for a minute. Stir in ground turmeric, ground coriander and red chili powder. Fry for a minute. Add mangoes, prawns and enough salt. Pour thin coconut milk and enough water to make thick sauce. Cook, covered, for 6-7 minutes Stir in thick coconut milk, and cook, covered, for another 2 minutes. Garnish with more curry leaves. Serve hot.