Clean thoroughly and blanch the spinach in 1/2 a cup of water. Add little salt to the spinach. Let it cool. Then blend it to make a puree. Keep it aside. In a large saucepan, pour 3 tbsp. of oil. When hot, add the garam masala. Then add onions and saute till golden brown. Next add crushed ginger-garlic and saute. Now add chopped tomatoes and saute till the oil leaves the masala. Add turmeric, chilli powder, salt and fry for a while. Now add the cleaned meat to this and saute for 10 mins. Add 2.5 cups of water and let the meat cook (either in pressure cooker or on slow fire).When the meat is cooked, add the spinach puree, cumin powder and let it cook on a low flame for about 10 mins.