• Preheat the oven to 180° Celsius
• Place the onion, thyme, bay, peppercorns, star anise and leeks into a roasting dish
• Push everything together then place the gammon on top
• Pour in the cider and place into the oven
• Leave to cook for 90 minutes
• Remove from the oven and set aside to cool for 30 minutes

For the glaze

• Place the maple syrup, soy sauce, mustard, cloves, star anise and sage into a small saucepan
• Simmer over a medium temperature until thick

To finish

• Preheat the oven to 200° Celsius
• Take the gammon out of the roasting dish and drain the liquid into a saucepan
• Place the saucepan onto the stove over a medium to high temperature and leave the liquid to thicken to use as a gravy
• Peel the top layer of fat off the gammon and place under the grill for 10 minutes to make crackling
• Score the the fat layer on the gammon using a sharp knife
• Return the gammon back to the roasting dish and baste the top with the glaze
• Place the roasting dish in the oven and cook for a further 30 minutes, basting the gammon every 10 minutes
• Remove from the oven and leave to rest before slicing and serving