Add turmeric to the mutton or lamb and rub all over. Set aside.
Heat oil in a pressure cooker (electric or stovetop) and saute fennel seeds, bayleaf, cinnamon, cardamom and cloves for a minute.
Add green chilli, onions and ginger garlic paste. Cook this for 7-8 minutes till the onions are translucent.
Add tomatoes, coriander powder, mutton masala (or meat masala) and salt and cook for 5 minutes till the tomatoes break down slightly.
Add mutton, potatoes and a cup of water and put the lid on. If using a stovetop pressure cooker, cook on high pressure for 30-40 minutes (5-6 whistles).
If using an electric pressure cooker or an instant pot, cook for 25 minutes and let pressure release naturally.
Once the pressure is released, open the lid and switch on the flame again.
Add a little water if the gravy is too thick.
Stir in garam masala, kasuri methi (if using) and ghee and simmer for another 4-5 minutes.