Scatter the Coriander Seeds onto a baking tray and roast in the oven for 7-8 minutes. Remove and allow to cool.
Using a pestle and mortar, grind the Coriander Seeds and then add the remaining herbs and spices and grind until thoroughly mixed.
Transfer to a large bowl, then stir in the yoghurt and lemon juice.
Score each chicken breast 4 times with a sharp knife and add to the marinade, turn to coat thoroughly. Cover and leave to marinade for 30 minutes, or for best results overnight in the refrigerator.
Pre-heat the grill to a medium heat. Place the marinated chicken breasts on a wire rack and grill for 20-25 minutes, turning regularly, until the juices run clear and the surface has taken on a slight blackened appearance. Ensure chicken is piping hot and cooked through before serving.