Combine all marinade ingredients in a large gallon plastic bag, mixing thoroughly. Chop chicken into bite size pieces and marinate overnight.

Heat oil in large saucepan, then add chicken. Stir fry for about five minutes, then remove from pan and set aside

In same pan, heat ghee and add onions, cooking until they sweat. Add garlic and ginger, saute until aromatic.

Add coriander, garam masala, and cumin and saute for a minute, then add tomatoes, chilli powder, and salt. Simmer for 10 minutes.

Remove pan from heat, then use a stick blender or regular blender to puree sauce.

Return blended sauce to pan, then add cream and sugar. Return chicken and juices to sauce and combine. Simmer for another 10 minutes, then serve.