Marinate the mutton with curd, salt, turmeric powder, red chilly powder and mustard oil for 2 hours or overnight in the refrigerator.
In a pressure cooker add mustard oil, fry the potatoes with a little salt and turmeric powder to golden brown, take it out.
To the same oil add cumin seeds, bay leaf, Cinnamon, cloves, black and green cardomom.
Add sliced onions and a pinch of salt. Cover and cook till the onions turn translucent.
Add ginger garlic paste and green chillies.
After 2 minutes add the chopped tomatoes.
Once the tomatoes turn soft add the marinated mutton.
Add the dry spices, salt, sugar, cumin powder, coriander powder and turmeric powder.
Keep stirring and sauteing till the oil starts releasing from the sides, take almost about 10 minutes on a medium flame.
Add a little water and pressure cook for 10-12 minutes on a low flame after the 1st whistle.
Release the pressure, add the fried potatoes and pressure cook for another 5-7 minutes on low flame.
Allow the pressure to release on it's own.
Open the lid, sprinkle some Bengali garam masala.
Serve hot with rice.
