Combine yogurt, ginger, garlic, lime juice, cumin powder, coriander powder, garam masala, paprika, chili powder and salt in a bowl, Stir in the chicken. Cover and place in fridge for 2 hours to marinate.
Heat vegetable ghee in a nonstick frying pan over medium heat. Cook onion, stirring for 2-3 minutes or until soft. Add chicken and cook until browned. Stir in tomato, tomato puree and cashew nut butter, bring to a boil, lower heat and leave to simmer for 15 minutes. Stir in the cooking cream and simmer for additional 5 minutes.