Preheat oven to 300°. Place rack in shallow roasting pan. Place ham on rack; reserve glaze packet for another use. Let ham stand at room temperature for 20 minutes.

Meanwhile, for sauce, combine apple cider, onion jam, pear preserves and mustard in a medium saucepan. Bring to a boil; reduce heat to medium. Cook for 4 to 6 minutes or until sauce coats the back of the spoon, stirring frequently. Remove from heat.

Cover ham tightly with foil. Bake for 2 hours to 2 hours 50 minutes or until ham reaches 140°, uncovering ham and brushing with ½ cup of the sauce during the last 20 minutes of baking.

Transfer ham to a serving platter. Loosely cover with foil and let stand for 20 minutes. Brush with ¼ cup sauce before serving. Serve with remaining sauce.