In a medium bowl, combine the packed brown sugar, maple syrup, Dijon mustard, and the ground spices (if using). Add the entire can of pineapple chunks (or tidbits), including all the juice, stirring until the mixture is thick and sticky, like wet sand.

Place the spiral ham cut-side down into the well of the slow cooker. Generously spoon about 1/3 of the glaze mixture evenly over the top of the ham, making sure it seeps down into the pre-cut slices. Pour the remaining glaze around the base of the ham, allowing it to pool beneath.

Cover the crock pot and cook on LOW for 4 to 5 hours. The ham is already fully cooked, so we are essentially just heating it through and ensuring the internal temperature reaches 140°F (60°C) while marrying those glorious flavors.

During the last 30 minutes of cooking, carefully open the lid (watch out for steam!). Spoon the glaze mixture from the bottom of the pot over the top of the ham again. Once ready, remove the ham from the slow cooker and let it rest on a cutting board, covered with foil, for 10-15 minutes before serving.

While the ham rests, transfer the liquid into a small saucepan and bring it to a simmer. Whisk in a cornstarch slurry (1 tablespoon cornstarch mixed with 2 tablespoons cold water) until the sauce thickens slightly into a glossy, sweet finish. Serve alongside large slices of ham.