Begin by making up the marinade mixture. Measure the yoghurt into a bowl, then crush the cumin and coriander seeds together with the cardamom pod in a pestle and mortar (failing that, use the end of a rolling-pin and a basin) and add them to the yoghurt. After that add the rest of the marinade ingredients and stir well to get everything thoroughly combined. Now cut the chicken breast into medium-sized chunks (you should get about six or seven), then add them to the marinade and stir again to get the chicken pieces properly coated. Cover the bowl with clingfilm and leave in the fridge for at least 3-4 hours to marinate.
You could, if you wanted to, start this off the night before.
When you're ready to cook, pre-heat the grill to high. Then thread the pieces of chicken on to a skewer, if possible a flat one, which makes it so much easier to turn the kebabs. Don't pack them too tightly, give them room for the heat to get to them. If any of the chicken pieces are flat rather than chunky, fold them over before threading them.
Now set the skewer so that the ends rest on the side of a gratin dish (or similar shallow dish) to make sure any juice drips into the dish and not the grill. Now drizzle a little oil over the chicken pieces and place the dish under the grill so that the chicken is 1-2 inches (2.5-5 cm) from the heat.
Grill for 10-15 minutes, turning the skewer a couple of times, or until the spicy crust has charred a bit all over and the chicken pieces are cooked through.
Serve on a bed of rice (cooked perhaps with a little onion and pepper) and some mango chutney.