Rinse the mutton a couple of times. Drain all water and set aside.
Blend ginger, garlic, coriander leaves, and yogurt to make a fine paste.
Apply this paste/mixture to the mutton and mix is properly. Set it aside to marinate for 1/2 hour.
In a pan dry roast poppy seeds, red dry chilies, black pepper, coriander seeds, cumin seeds, cloves, cinnamon for couple of seconds.
Take off heat. Allow it to cool and then grind it to a powder in a coffee/spice grinder.
Next, heat oil in a pressure cooker. Add bay leaves and chopped onion. Saute the onion until golden brown.
Add chopped tomatoes and saute for a couple of seconds.
Next, add the spice mixture/masala and mix it.
Now add the mutton pieces. Add salt, turmeric, and mixture it properly. Add water.
Pressure cook this for until 10 whistles or approx 30 mins.
Switch of the heat. Once the pressure has subsided removed the lid of the cooker.
Add Vaatan (coconut paste) and mix properly.
Cook on slow for another 15 mins until the coconut paste has completely blended and the curry has become thick.
Remove from heat. Serve hot with some rice vade, bread or rice.
You can use Instant Pot of cook the mutton beforehand. Use the saute mode and follow steps 3 to 6. Close the lid and select Meat/Stew mode to cook the mutton until tender. Follow rest of the above mentioned steps.