Pour ⅓ cup water around the sides and bottom of the ham.
In a saucepan over medium heat, combine Dijon mustard, brown sugar, honey, nutmeg and cinnamon. Whisk constantly and cook for 2-5 minutes, or until sugar dissolves.
Pour glaze over ham in the slow cooker.
Cover and cook on low for 2-4 hours or until heated through if your ham is precooked. If it's not precooked, it will take 4-6 hours.
When ham is done cooking, remove it from the slow cooker and cut into slices.
Pour the ham drippings through a strainer and into a medium saucepan.
Whisk together 2 Tablespoons cornstarch and 2 Tablespoons of water then whisk into drippings over medium-high heat.
Continue cooking and whisking until gravy comes to a boil and reaches desired thickness.
Serve gravy with ham.
Notes
If the top of your ham is sticking out of your slow cooker, simply use some sheets of foil and create a tent to hold in the heat around the sides of the ham then pinching closed at the top. Place a thick, clean cloth on top of the foil tent to hold in the heat and then place the lid to the slow cooker on top.Swap the cinnamon and nutmeg with cloves for a more intense flavor profile.Substitute the honey with maple syrup for a maple glazed ham. Consider adding a touch of orange juice or pineapple juice to the glaze for a fruity twist.Use a meat thermometer to check if your ham is fully cooked. The internal temperature should read 150°F.