Take a pressure cooker, add oil and heat it.
Add whole spices such as cinnamon stick, cloves, cardamoms, bay leaf, cumin seeds and saute well.
Add chopped onions and saute until they turn soft and translucent.
Add ginger garlic paste and saute to get rid of raw smell.
Add the mutton/lamb pieces into it.
Roast them well until color changes.
Add dry spices such as red chili powder, salt, turmeric powder, black pepper corn powder, coriander powder, garam masala powder.
Mix well.
Add the chopped tomatoes, mix well.
Cook the gravy for 5-10 minutes until the tomatoes turn soft.
Stir in between and cook the gravy for another 5 minutes.
Add a cup of water and mix.
Cover the lid and pressure cook the mutton until it gets tender or for 3-4 whistles.
Switch off the flame.
Release the pressure naturally.
Remove the lid and thicken the gravy a bit on low flame.