Fry the onions in the butter till golden and remove from the pan, drain them but save the cooking fat. turn of the cooker.
Put 3/4 of the onions in a blender and process them with all of the ingredient EXCEPT FOR THE CHICKEN.
With a fork, prick the chicken all over and rub the spiced onion mixture into the flesh (yes use your hands or get the kids to do it). Set aside for a couple of hours to allow the flavour to develop in the meat.
Pre-heat the oven to 350°F, arrange the chicken on a roasting dish, pour the drained fat over the chicken, arrange the remaining onions on top of the meat and cook for 1 hour.