Remove the ham from the refrigerator 1 hour before cooking to let it come to room temperature. This helps it to cook evenly.
Preheat oven to 325°F with a rack in the lower third of the oven (remove any other racks that would be in the way of the ham).
Remove the ham from the packaging. If there is a glaze packet or plastic disk covering the bone, remove and discard them. Place ham in a roasting pan or large, deep baking dish, cut side down. Cover the pan/ham tightly with foil. (You will probably need to use a few pieces of foil to fully cover the ham.)
You will now bake the ham most of the way at 325°F, covered with foil. When the ham has only 20 minutes of cook time left, you will uncover it, and start brushing on the glaze (see the steps below). The total bake time for the ham is about 10-11 minutes per pound. (A 10 pound ham will take about 1 hour 40 minutes to 2 hours total.) Set a timer for 20 minutes before the ham should be fully cooked to start checking on it.
While the ham is in the oven, make the glaze: In a medium saucepan, combine the brown sugar, orange juice, honey, Dijon mustard, butter, allspice and ground cloves. Heat over medium heat, whisking often, until glaze starts to boil. Then reduce heat to medium-low and continue cooking at a low boil, whisking often, until the glaze thickens, 5-7 minutes. Remove from the heat.
When the ham has about 20 minutes of cook time left and has reached an internal temperature of 115-120°F, take it out of the oven and increase the oven temperature to 400°F. Uncover the ham and brush on half of the glaze, trying to get some in between the slices. Return the ham to the oven and bake, uncovered, for 15 minutes. Then brush on the remaining glaze, and bake for 5 more minutes, or until ham reaches 140°F when measured with an instant read thermometer.
Remove ham from the oven and let it rest for 15 minutes. Then slice and serve.