1. To make glaze, combine juices and sugar in a small pot. Set over medium, medium-high heat and bring to a simmer. Simmer juice until reduced to 3/4 cup. Measure juice to ensure you have 3/4 cup. If you have more than that, simmer it a while longer until you do. Or, if you’ve reduced it too much, top up with water until you have 3/4 cup (see Options).

2. Preheat oven to 325 F. Combine coriander, paprika, cumin, garlic powder and onion powder in a small bowl. Trim ham of any excess tough outer skin and some of the excess fat, if desired. Set ham, fatty side up, in a parchment paper-lined shallow roasting pan. Score top of ham in a diamond pattern, making shallow cuts about 1-inch apart. Sprinkle and rub ham all over with the spice mixture (see Options).  Bake ham, uncovered, 80 minutes.

3. When ham has baked 80 minutes, brush with 1/3 of the glaze. Bake 10 minutes more. Brush with 1/3 more of the glaze and bake another 10 minutes. Now brush with remaining glaze and bake another 10 minutes, or until ham is richly coloured and piping hot, about 140 F (60 C) or above when tested in the very centre with an instant-read meat thermometer. Transfer ham to a cutting board, tent with foil and rest 10 minutes. Now slice, arrange on a platter and serve.

Options: You can make the glaze a day before needed. Once made, transfer to a bowl, cool to room temperature, cover and refrigerate until needed for the ham. You can score the top of the ham, set it in the roasting and rub it with the spice mixture many hours before cooking it. If you do that, keep ham refrigerate until ready to bake.