1. Preheat oven to 325oF. Remove wrapping from ham and rinse and dry well. Stand in roasting pan, skin side-up.
2. With a sharp paring knife, score a diamond-shaped pattern into skin of ham. Spread a thin layer of mustard over skin. Pat brown sugar over mustard, pressing firmly to adhere. Drizzle honey over the top in an even layer.
3. Bake until ham is well glazed, spooning any mustard and sugar glaze that slides into roasting pan back over ham, about 30 minutes. Transfer ham to serving platter; let cool at least 45 minutes. Slice ham and serve warm.