Grind onion, green chillies, garlic cloves, ginger, black peppercorns and coriander seeds in a grinder jar to form a smooth paste.

Sieve the ground paste to remove any coarse bits.

Marinate the mutton pieces in a mixing bowl with the ground paste, degi mirch powder and salt. Cover the bowl with a cling film or a plate and refrigerate for at least 2 hours.

Heat oil in a pan on high heat. Add the sliced onions and fry them until golden brown. Remove them from the pan, coarsely grind them in a blender and set them aside.

Heat ghee in a large pot over medium-high heat.

Add the dry spices- cinnamon stick, green cardamoms, cloves, black peppercorns, bay leaves, and star anise and stir them for a few seconds.

Add the curd and stir continuously for 3-4 minutes until the curd begins to curdle.

Add nutmeg powder and mace powder and stir to mix.

Add the marinated mutton to the pot and mix well to coat the meat with the spices. Cover and cook the mutton on high heat for approximately 8-10 minutes, allowing it to sear.

Add the barista to the pot and mix well. Cook for 4-5 minutes, stirring occasionally.

Add water to the pot and mix. Bring to a boil, cover with a lid and cook on low heat until the mutton is tender. (approx 1.25 hours). Stir occasionally.

Check the seasoning and adjust to taste.

Add Kewra essence and cashew paste and mix well. Adjust the consistency of the gravy by adding water if needed.

Garnish with fried onions (barista) and serve hot with roti or naan.