Marinate mutton pieces with turmeric powder and salt for one hour.
Heat oil in a pressure cooker, add onions and sauté till light golden in colour. Add garlic and ginger and sauté for another two minutes.
Add black pepper powder, cumin powder and marinated mutton and sauté well so that the masala coats the mutton pieces. Continue to sauté till the mutton pieces are well seared.
Add three cups of water and salt. Cover the cooker with its lid and cook, on medium heat, till eight whistles are given out. Once the pressure reduces completely, open the lid and cook till dry. Serve hot.