1/2 cup apricot jam
1/2 cup Dijon mustard
1/2 cup packed light brown sugar
Freshly ground black pepper
One 4- to 5-pound spiral-cut ham
Whisk together the jam, mustard, sugar and 1/4 teaspoon black pepper in a small pot. Bring the mixture to a boil to melt the sugar, whisking occasionally. Reduce the heat to a simmer until the mixture thickens, about 2 minutes. Remove from the heat, and reserve.
Add 3/4 cup water to the insert of a 6-quart slow cooker. Place the ham in the insert on its side, and brush lightly with the glaze. Cover, and cook on low until the ham is hot throughout, 6 to 7 hours. Refrigerate the remaining glaze.
When the ham has about 10 minutes left to cook, reheat the glaze in a small saucepan over medium-low heat, stirring frequently.
Transfer the ham to a carving platter or serving dish, and brush with enough glaze to make a glossy, sticky coating. Slice, and serve with the remaining glaze on the side.