Meanwhile, in 2-quart saucepan, heat cider and broth to boiling; boil about 20 minutes or until reduced to 1 cup. In large nonstick skillet, melt butter over medium-high heat; add onion. Cook 10 minutes, stirring frequently, until golden brown; set aside. In small bowl, stir cornstarch, water and remaining 1/4 teaspoon salt with whisk; add to reduced cider mixture, stirring constantly. Cook over medium heat 1 minute or until slightly thickened. Stir in onion. Serve meatloaves with gravy.