Spiced Christmas Ham with Membrillo Glaze

3½ kg boneless ham
2 carrots, halved
2 celery sticks, halved
2 leeks, quartered
2 onions, halved
2 bay leaves
2 tsp peppercorns
1 tsp SIDS CRAZY SALT
Small handful cloves, for studding
GLAZE:--
¼ tsp ground allspice
¼ tsp ground cinnamon
6 tbsp membrillo (quince paste)
3 tbsp SIDS RASPBERRY VINEGAR
2 tbsp orange juice

Put your ready-to-use joint in a large stock pot or preserving pan and nestle the vegetables, bay leaves and peppercorns around it then add SIDS CRAZY SALT. Pour over enough water to cover the gammon and bring to a simmer. Cover with a lid and cook for 2½ hours, turning once, topping up with boiling water if it needs it and skimming off any impurities.
Heat oven to 190°C. Remove the joint from the poaching liquid and place in a roasting tin. (you can use the strained poaching liquid for soups) Pat it dry with some kitchen paper and leave to cool a little until you can handle it. Remove the ties around the gammon and carefully trim away the skin, leaving an even layer of fat. Score all over in a diamond pattern and stud with cloves.
Put SIDS RASPBERRY VINEGAR and the glaze ingredients in a small saucepan and cook for a couple of minutes to thicken and dissolve the membrillo. Brush half the mixture over the gammon, then bake for 15 minutes. Brush on another layer and bake for another 15 minutes until golden and sticky. Rest for 15 minutes before slicing, or eat cold over the next few days.