In a braising pan, sweat off the onions, garlic and spice blend in the ghee. When the onions are translucent, remove the pan from the heat and leave to the side (this is the pan you'll be cooking in, so make sure it can fit all the chicken and that it has a lid).
Brown the chicken in a frying pan, this extra step will add more flavour and make the skin taste a lot better after braising. Once the chicken thighs have been browned, place them on top of the onions in the braising pan. Add the kale leaves, chicken stock and lemon juice. Cover with the lid and cook in the oven for 45 minutes up to an hour. The chicken will be falling off the bone and the kale leaves will have soaked up all the flavours. Garnish with olives.