Add turmeric and 1 teaspoon salt to the mutton or lamb and rub all over. Set aside while you prep everything else
Heat oil in a pressure cooker (electric or stovetop) and saute fennel seeds, bayleaf, cinnamon, cardamom and cloves for a minute. Add two green chillies, onions and ginger garlic paste. Cook this for 10-12 minutes stirring occasionally till the onions are a deep brown.
Add tomatoes, coriander powder, meat masala and the remaining salt and cook for 5 minutes till the tomatoes break down slightly.
Stovetop Pressure Cooker: Add mutton, potatoes and two cups of water and put the lid on. If using a stovetop pressure cooker, cook on high pressure for 20-25 minutes (5-6 whistles).
Instant Pot: If using an electric pressure cooker or an instant pot, cook for 20 minutes on high pressurenand let the pressure release naturally or manually release the pressure after 15 minutes.
Once the pressure is released, open the lid and switch on the flame again. Add more water if the gravy is too thick. Stir in garam masala, kasuri methi (if using), remaining green chillies, julienned ginger and ghee and simmer for another 3-4 minutes.
Check and adjust seasoning. Let the curry rest for 15 minutes before serving.