If you don’t have a pot big enough for the whole ham then you can do this in the oven – just line a large roasting tin with foil and a wire rack and place the ham on top. Put the aromatics and cider under the ham and cover with a large tent of foil. Bring to the boil over a hob then transfer to a low oven (120˚C/100˚C fan/250˚F/Gas Mark ½) and roast overnight for about 12 hours. Keep the juices to make ham soup later in the Christmas period!