Butter chicken or murgh makhani is an Indian dish popular in Britain, Australia and many other countries that have a tradition of Indian restaurants.
It is a dish made by marinading a chicken overnight in a yoghurt and spice mixture usually including ginger, lemon or lime, pepper, coriander, cumin, chilli, methi, cumin and garlic.
The chicken is then roasted or baked.
A sauce is made from butter, tomatoes, almonds and various spices, often including cumin, cloves, cinnamon, coriander, pepper, fenugreek and sometimes cream. Once the sauce is prepared the marinaded and roasted chicken is chopped and added to it.
...but I didn't do any of that. I bought a package that had a paste for the spices, added chicken, water, milk and butter as per the package in the clip.