Thoroughly clean the mutton and set aside. Dissolve saffron with milk and set aside too.
Heat ghee (clarified butter) in a large and deep bottomed pan. Add bay leaf, cinnamon, cardamom, cloves and cook on low heat till the spices begin to crackle.
Now add mutton, turmeric powder, salt (as per your taste) and saute for 5-7 minutes on medium flame. Cook until all the water is dried up and the meat changes color.
Add 10 glasses of water. Now reduce the heat and cook covered on low heat till the mutton softens and is fully cooked. The water would have reduced to half by now. Add in more water if necessary.
Whip the yogurt and gently add it to the broth. Cook on low flame while stirring continuously to avoid curdling.
Add red chili powder and cook till the ghee starts separating on top.
Now add saffron milk and coriander leaves to the Yakhni soup and cook on low flame for a further couple of minutes. Remove from heat and rest for 5 more minutes before serving hot.