To make the glaze, place brown sugar, kaffir lime leaves, calamansi juice, calamansi soy sauce, rice wine vinegar, Chinese five spice, star anise, cinnamon and ginger into a medium saucepan. Bring to the boil and then reduce the heat to low and simmer for 20-30 minutes or until starting to thicken. Add the spiced rum and stir to combine. Cook for a further 5-10 minutes. You can make the glaze up to 3 days in advance and store in the fridge.

To prepare your ham, first remove all packaging. First you will need to remove the layer of rind, leaving behind the fat underneath. Cut a line or criss cross at the shank or small end of the ham and then carefully slip a small, sharp knife under the rind to loosen it from the fat. As mentioned above, if you anticipate having leftovers, you can keep the rind and cover the remaining ham with it for storage in the fridge.

When the rind is completely removed, use your knife to score all the way through the fat layer in a 2.5cm (1 inch) diamond pattern, following the curve/shape of the ham.

Preheat your oven to 160°C (320°F). Line a baking tray with aluminium foil.

Transfer the ham to the baking tray. If you have stored your glaze in the fridge, bring it back to just before boiling point. Using a pastry brush, glaze the ham all over generously. Place into the oven for 20 minutes.

Remove from the oven and glaze again every 20 minutes, rotating the baking tray so it cooks evenly. My 3kg ham took about an hour. Please refer to the cooking time suggested on the packaging of your ham. If your ham is colouring too quickly, you can cover it with some foil to prevent the glaze from burning.

To serve, I like to remove the cooked kaffir lime leaves (optional) and wrap the shank end in some baking paper and add some fresh herbs tied with twine for aesthetic reasons. To carve, pierce the ham with a carving fork and use a carving knife or serrated knife to carve slices, following the grain of the meat. Serve warm or at room temperature.