Make a green puree by blending garlic ginger, mint leaves, coriander leaves, spinach, green chillies and water. Heat oil in a pan and roast bay leaves, black cardamom, cinnamon stick, black peppercorns and cloves. Add chopped onion too. Add mutton to this and mix well. Add chopped tomato salt, all ground spice, black pepper powder and cumin powder. Pour a little water into this and let it cook well on a high flame. Add the freshly prepared green puree to this and mix. Cover the pan and let it cook for some more time. Once done, transfer the curry to the serving plate. Garnish with a green chilli and serve with a naan.