1.Heat butter and oil in saucepan, over medium-high heat. Add onion and cook for 5 minutes. Add onion and cook for 5 minutes. Add chicken and cook for 3 minutes.
2.Add garlic chilli powder, cumin, coriander, ginger and garam masala to saucepan. Stir to coat chicken with spices. Cook for 2 minutes.
3.Add passata, cream and sugar to chicken pan and bring to a simmer. Reduce heat to medium – low and simmer gently for 10 minutes until chicken is cooked through.
4.Remove butter chicken from heat and stir through yoghurt. Season to taste.
5.Spoon into serving bowls and garnish with coriander and pistachios. Serve with rice and naan bread.