Preheat oven to 325 degree F. Trim any excess fat from ham. Score ham with diagonal cuts in a diamond pattern. Place on a rack in a shallow roasting pan. Insert a meat thermometer. Bake until thermometer registers 140 degree F (1-1/2 to 2-1/4 hours).
Meanwhile, in a large saucepan combine apple cider, honey, vinegar, mustard, and chili powder. Bring to boiling; reduce heat. Boil gently, uncovered, about 15 minutes, stirring frequently. (Watch carefully, as mixture will bubble up.) You should have about 2 cups of mixture. Remove half of the mixture to a small bowl. Stir in butter and 1/4 teaspoon of the pie spice. Set aside for sauce. Bring remaining mixture in saucepan to boiling; reduce heat. Boil gently for 5 minutes or until mixture is thickened and reduced to about 1/2 cup, stirring frequently. Stir in remaining 1/4 teaspoon pie spice; use for glaze. If glaze should set up before using, cover and reheat in a microwave-safe dish on 100 percent power (high) for 1 minute or until warm.
Brush ham with glaze the last 20 to 30 minutes of baking. Reheat cider sauce in a small microwave-safe bowl for 1 minute on 100 percent power (high) or heat in a small saucepan. Pass sauce with ham. Makes 16 to 20 servings.