Prepare the glaze by mixing brown sugar, honey, Dijon mustard, apple cider vinegar, ground cloves, ground cinnamon, and black pepper in a mixing bowl. Whisk until the mixture is smooth and well combined.
Place the fully cooked ham in the crock pot. If necessary, trim any excess fat.
Pour half of the glaze mixture over the ham, making sure to cover it evenly. Reserve the other half of the glaze for basting.
Cover the crock pot and cook on low for 6 hours.
Every hour, baste the ham with the reserved glaze to enhance its flavor and moisture.
After 6 hours, check the internal temperature of the ham; it should reach at least 140°F (60°C).
When the ham is done, remove it from the crock pot and let it rest for about 15 minutes. Slice and serve.