Place yoghurt, garlic, cumin, coriander, garam masala and chilli powder in a glass bowl. Add chicken. Stir to coat. Cover and refrigerate for 2 hours.

Heat butter and oil in a heavy based saucepan over medium - high heat. Add onion. Cook stirring occasionally for 3 - 4 minutes or until softened.

Add chicken mixture to pan. Cook, stirring for 5 minutes or until chicken just starts to change colour.

Add tomato puree and stock. Cover, bring to the boil, reduce heat to low. Simmer, stirring occasionally for 10 minutes or until chicken is tender and mixture had thickened slightly.

Stir in cream. Simmer for a further 5 minutes or until heated through.

Serve with steamed rice