Marinate chicken with 1 cup of vinegar for 1 hour, then wash and dry thoroughly In the karahi, add one cup of oil and fry chicken on high flame for 10 minutes.
Add in the cup of whole garlic, 2 cups of mint leaves, salt and chilli powder. Fry for another 10 minutes on high flame.
Add in the tomato puree and cook on high flame till dry and oil comes to the top.
Lower the flame and add one cup of mint leaves and the brown sugar.
Ready to serve with hot naans.