Fill a large pan with water and place the gammon inside; submerging completely.
Add the orange rind, onion, bay, thyme, star anise, black peppercorns and celery and bring to the boil.
Immediately reduce the heat and simmer gently for 1 hour 45 minutes.
20 minutes before the gammon is ready preheat the oven to 200°C and make the glaze.
In a saucepan on a medium heat, melt 25g Lurpak and add the sugar, wholegrain mustard, English mustard, orange zest, salt and pepper.
Stir with a wooden spoon until all the ingredients are incorporated and the sugar has dissolved. Be careful not to let the mixture boil.
Once the gammon has simmered for 1 hour and 45 minutes, remove it from the pan and allow to cool for 15 minutes.
With a sharp knife carefully remove the skin - avoiding taking too much of the fat with it.
Score the fat to create diamond shapes then stud the centre of each diamond with a whole clove.
Place the gammon in a foil-lined roasting tray then spoon the glaze over the fat.
Put in the preheated oven for a total of 20 minutes basting once during that time.
Remove from the oven, slice and serve.