Add the gammon, cranberry juice, onion, carrot, bay leaves and mixed spice to a slow cooker. Cook on low for 7 hours or 3.5 hours on high. Ensure the gammon is sat on top of some vegetables, fat side up and the cranberry juice covers the gammon.
Towards the end of your slow cooker time, heat your oven to 190C. Whilst heating, mix together the mustard, sugar, marmalade and cider vinegar. Gently heat the mixture on a low heat to loosen it up.
Once cooked, remove the gammon from the slow cooker and take the fat off. It should easily pull off without a knife. Score a diamond pattern into the remaining fat and press a clove into each cross-section. Place back on top of the gammon.
Cover the gammon in half of the glaze. Slice the orange and add them on top. Use cloves to hold them in place if needed.
Bake in the oven for 10 minutes, then add the remaining glaze. Bake for a further 10 minutes. Serve with the trimmings and enjoy!
