HEAT ham according to package directions. COMBINE orange marmalade and brown sugar in small bowl until blended. Remove ham from oven 30 minutes before end of suggested bake time. Brush glaze over ham. BAKE an additional 30 minutes. Remove ham from oven and let rest 5-10 minutes. Spoon pan juices over ham and serve.
For a thicker sauce to serve with baked ham: Drain pan juices into a small saucepan. Heat to boiling; reduce to medium heat. Stir 3 tablespoons cornstarch into 3 tablespoons cold water until smooth. Blend into pan juices, stirring constantly until thickened. Spoon warm sauce over ham and serve.