1. Melt the butter in a pan. Add the cinnamon stick and fry gently until aromatic. Add the fresh ginger and green chilli and fry for 2-3 minutes.
2. Add the ground cardamom, cayenne pepper, garam masala and stir. Add the tomato puree and stir to combine. Whisk in the fresh cream and simmer for 2-3 minutes, stirring continuously.
3. Add the fenugreek leaves, and season to taste. (You can also add a little sugar / honey, if required). If sauce is too thick add a splash of water. Now add the cooked Tandoori Chicken and simmer for 5-10 minutes to heat thoroughly.
4. Serve hot, garnished with fresh coriander, and accompanied by hot roti or paratha.