Take ham out of the fridge 1 hour prior.
Preheat oven to 160C / 320F (standard) or 140C / 285F (fan). Arrange shelf in lower third so the ham will be sitting in the centre of the oven (not right at the top of the oven, this causes more uneven cooking on surface).
Remove the rind (skin) of the ham, ensuring you leave the fat on (Note 5 for steps, photos in post and video above)
Scoring - Cut 2.5cm / 1" diamonds into the fat (don't cut into flesh).
Place brown sugar, honey, mustard, cider vinegar, pepper and Spices into saucepan over medium high heat. Simmer and stir until sugar is dissolved.
Place rack in a baking pan and place ham on rack.
Baste all over with the glaze (except the handle), including underside and the cut face. Reserve remaining glaze for basting.
Bake for 15-20 min per lbs, basting every 20 minutes with reserved glaze (Note 6) and pan juices, until caramelised and the internal temperature is 60C/140F. (Note 7)
Stick bits of foil on parts that are browning too quickly, and you can even lower the oven temp. (Note 8)
Rest ham for 15 to 30 minutes+, basting generously with the pan drippings - use it like paint to make your ham beautifully bronzed all over with a thick glaze. (Note 9)
Leftovers: See list in post for recipe using leftover ham and ham bone!
Storing: Will keep for at least a week in the fridge if properly stored using a water-vinegar soaked ham bag or pillowcase. Otherwise freeze - don't forget the bone! See How to Store Glazed Ham for directions.
