Chicken tikka masala

Ingredients
For the chicken and marinade:
1 whole chicken (1.3 to 1.8kg) cut into 10 pieces
Salt and freshly ground black pepper
240ml natural yoghurt
2 tbsp smoked paprika
1 tbsp ground coriander
1 tbsp ground cumin
2 tsp cayenne pepper
1 tsp lemon zest
½ tsp ground cinnamon
3 cloves garlic minced
2.5cm piece ginger peeled and grated
For the sauce:
2 tbsp vegetable oil
30g butter
2 cloves garlic crushed
1 large onion sliced
1 tbsp tomato puree
1 tbsp smoked paprika
2 tsp garam masala
400g tin fire-roasted chopped tomatoes
15ml red wine vinegar
120ml double cream Fresh coriander chopped

Directions
For the chicken and marinade:
Sprinkle the chicken pieces with salt and pepper. Combine the yogurt with the paprika coriander cumin cayenne lemon zest cinnamon garlic and ginger in a mixing bowl. Mix together well then pour into a resealable plastic bag. Add chicken pieces and shake around to coat all the pieces evenly. Place in the refrigerator and marinate for 1 hour.
Heat a grill to high. Wipe down the grates with an oil-blotted paper towel to create a nonstick surface. Remove the chicken from the marinade and wipe off any excess. Grill the chicken pieces until well-marked 3 to 4 minutes per side. Remove to a plate and set aside.
For the sauce
Set a casserole or Dutch oven over a medium heat. (Alternatively you can cook in a pressure cooker. Simply cut the cooking time in half and cook over medium heat with medium pressure.) Coat with the oil and add the butter.
Add the garlic and onions. Cook until translucent and fragrant 3 to 4 minutes. Add the tomato puree paprika and garam masala. Cook for 2 to 3 minutes to toast the spices and cook the tomato paste.
Add the chopped tomatoes vinegar and grilled chicken pieces. Stir well and simmer until the chicken is tender 25 to 30 minutes.
Finish the sauce by stirring in the double cream. Season with salt and pepper and garnish with the coriander.