Preheat your oven to 325°F (163°C).
Place the ham on a sturdy cutting board. Using a sharp knife, score the top of the ham by making shallow cuts (about ¼ to ½-inch deep) in a crisscross pattern. Ensure the cuts are 1-2 inches apart, forming a diamond or checkerboard pattern.
Position the scored ham in a roasting pan with the scored side facing up.
In a small saucepan over medium heat, combine the brown sugar, maple syrup, Dijon mustard, apple cider vinegar, ground cloves, ground cinnamon, and optional orange zest. Stir frequently until the sugar dissolves, and the sauce slightly thickens.
Pour half of the glaze over the scored ham, reserving the remaining half for later. Tent the ham loosely with aluminum foil.
Roast the ham for 2 hours, basting with pan juices every 30 minutes.
A few minutes before removing the ham from the oven, reheat the reserved glaze in the saucepan until heated through (3-5 minutes).
Once the ham reaches an internal temperature of 145°F (63°C), remove it from the oven. Pour the warm glaze over the ham. Allow the ham to rest for about 15 minutes before slicing.