Heat ghee in a pressure cooker and fry mutton pieces for 5 minutes on medium heat till the juices are sealed.
Remove the mutton pieces and add a little more oil if needed. Add all the whole spices and fry sliced onion till light golden followed by ginger and garlic paste.
Now add chopped tomatoes, green chilies, 2 teaspoon coriander powder, 1 teaspoon cumin powder, 1/4 teaspoon turmeric powder and cook for two minutes on low flame.
Return the mutton pieces to the pressure cooker and mix with onion and tomato mixture till well combined. Add salt and 1 cup of water and close the lid. Pressure cook the mutton for 15 minutes.
After 15 minutes turn off the heat and safely open the lid. Check the doneness of mutton as it should be almost cooked (not over cooked). Cook more if needed.
Then add chopped fenugreek (methi) leaves, 2 tablespoons crushed black pepper, 1/4 teaspoon garam masala powder, 1 tablespoon lemon juice, 2 tablespoon cashew nut paste, and 1/2 cup cream. Mix well and add some water if needed.
Cook the curry on low heat for 10 minutes and finally add chopped coriander leaves.
Serve hot with rice or roti.