Rinse ham and pat dry with paper towels.
Score ham in a criss-cross pattern and set aside,
Tip the rest of the ingredients into a saucepan and place on a high heat.
When glaze begins to bubble, lower heat just above medium and stir till reduced to one third. The glaze should be thick and concentrated. Be careful, it will be very hot.
Strain glaze and allow to cool.
Fill roasting tin with water up to just below the wire rack.
Place ham on the rack in the roasting tin.
Generously mop ham with glaze and place in a preheated oven at 325.
Allow to cook for approx. 1 hour 45 minutes or 15-18 mins per pound.
Generously mop ham with glaze every 30 minutes.
Cover top of ham with foil if it begins to brown too quickly and then remove for the final 10 mins.
Serve hot or cold.