Preheat the oven to 325°F
Place the bone-in ham in a roasting pan
Score the surface of the ham in a diamond pattern if desired
Cover the ham loosely with foil
Bake until heated through, about 15 to 18 minutes per pound
Remove the foil during the last 20 to 30 minutes if glazing
Brush with glaze if using
Continue baking until the glaze is set and the internal temperature reaches 140°F for pre-cooked ham
Remove from the oven
Let the ham rest for 15 to 20 minutes
Slice and serve