Heat oil, add whole garam masala, add the sliced onions when the garam masala splutters.Saute till golden brown.Add mutton and saute on high heat for 5 mins.Add ginger-garlic paste, reduce heat and add the coriander, chilli, cumin powder.Saute on medium heat till the water dries up in the meat.Add the cashewnut paste, tomato puree and saute till oil separates.Add 3 cups of water and cook till mutton is done.Whisk the yogurt, add to the mutton.Add garam masala and cinnamon powder.

When it starts boiling, remove from heat immediately.Serve garnished with chopped coriander.