Preheat oven to 350 degrees Fahrenheit. Pour one cup of water into the bottom of the roasting pan, then set aside.
Prep the Ham: Combine the brown sugar, salt, onion powder, garlic powder, black pepper, smoked paprika, and cayenne pepper in a small bowl and mix together until uniform.
1 tablespoon brown sugar, 1 ½ teaspoon sea salt, 1 ½ teaspoon onion powder, 1 teaspoon garlic powder, 1 teaspoon black pepper, ½ teaspoon smoked paprika, ½ teaspoon cayenne pepper
Use pastry brush to spread the mustard all over the ham in a thin layer then coat with the mixed seasonings. Place the ham, cut side down, inside the pan then cover snugly with aluminum foil before transferring to the oven to bake for 10 minutes per pound.
2 tablespoons Creole mustard, 6-8 pounds bone-in, spiral-sliced smoked ham
Make the Bourbon Peach Glaze: While the ham roasts, pit and slice peaches, leaving the peels intact, and add to a small saucepan with juice of half a lemon, brown sugar, cinnamon, ginger, and nutmeg over medium heat.
2 pounds fresh peaches, ½ lemon, ½ cup brown sugar, 1 teaspoon ground cinnamon, ¼ teaspoon ground ginger, ¼ teaspoon ground nutmeg
Stir to coat the peaches in all the ingredients then cook the mixture down until it is jammy and thickened (about 10 minutes), stirring occasionally. Remove from heat then stir in the bourbon.
⅓ cup bourbon whiskey
Let the mixture cool for about 30 minutes then transfer to a blender or food processor and pulse until liquified.
Finish the Ham: Remove ham from the oven and increase oven temperature to 400 degrees Fahrenheit. Remove the aluminum foil and coat the ham with about half of the glaze.
Once the oven reaches temperature, return the ham to the oven, uncovered, and cook for another 30 minutes, or until the internal temperature reaches 140 degrees Fahrenheit, basting with the pan drippings every 10 minutes--make sure to get the sauce and drippings in between the ham slices as they open up during cooking. If the top of your ham starts to char, tent a piece of foil over it and continue roasting in the oven. Remove ham from the oven, baste it with the pan drippings, then allow it to rest for about 15 minutes so that the juices can redistribute and your ham slices will be juicy. Serve with remaining glaze.