Place all the ingredients except the chicken in a food processor or blender and whizz to a smooth paste. Rub the paste all over the chicken, then place in a non-metallic bowl and cover with clingfilm, or place in a plastic food bag and seal. Leave to marinate in the refrigerator for at least 3 hours and preferably overnight.
Tip the chicken on to a shallow baking tray and place in a preheated oven, 200°C (400°F), Gas Mark 6, for 45 minutes or until the chicken is lightly charred and cooked through, turning once. Serve with salads of your choice.