Put the gammon joint into a flameproof casserole a little larger than the joint, add the carrot, onion, bay leaves and peppercorns, the cider and enough water to just cover the joint. Bring to the boil then add the lid and transfer to a preheated oven set to 190°C/375°F/Gas 5 and cook for 35 minutes per 500g/1lb 2oz.
Lift the joint out of the pan and transfer to a small roasting tin, allow to cool for a few minutes then cut away the rind. Score the fat underneath in criss cross lines with a knife then insert a few cloves into the squares of fat.
Mix the honey, mustard and ground cloves then spread this over the fat. Add two ladlefuls of the cooking liquid to the base of the roasting tin then return the joint to the oven, uncovered for 30-35 minutes, basting once or twice with the cooking juices until a deep brown.
If serving hot, transfer the joint to a serving plate, carve into slices and serve with spoonfuls of the honied cider pan juices. If serving cold, leave the ham to cool and serve sliced with salad and pickled plums, see below.
Pour the vinegar into a medium sized saucepan, add the honey, sugar, garlic, chilli, salt, peppercorns and half the herbs and bring to the boil. Simmer over a medium heat for five minutes until syrupy.
Meanwhile, wash, dry and prick the plums with a fork then pack into a warmed dry 750ml/1 ¼ pint jar with the remaining herbs, pressing the plums together tightly.
Lift the cooked herbs from the vinegar with a fork and discard then pour the hot vinegar mixture quickly over the plums making sure the fruit are covered by the vinegar. Close and seal the lid. Leave to cool then store in the fridge, ideally leave for two weeks so that the flavours can develop before eating with cold sliced ham.