Cook the mutton pieces with salt, a pinch of turmeric powder and half a spoon of vinegar. Heat oil in thick-bottomed pan. Splutter whole peppercorns and fennel seeds. Add curry leaves, onions and ginger-garlic paste. Sauté well. Add all the dry masala powders, vinegar, salt and mix well. Add the mutton pieces and fry for 2 minutes. Add one cup of water, reduce heat to minimum and let the gravy reduce till it coats the mutton pieces. Add chopped coriander leaves, half a teaspoon of coconut oil, close with a lid and keep aside for a few minutes. Serve hot with paratha/ chappathi/ appam.