Chicken Pot Pie

1 (15-ounce) package pie crusts

1/4 cup butter

1/3 cup chopped onion

1/3 cup flour

3/4 teaspoon salt

1/4 teaspoon black pepper

1 1/2 cups chicken broth

1/2 cup milk

3 cups cooked, cubed chicken

2 cups mixed vegetables

Heat oven to 425°F. Place pie crust in 9-inch pie pan. In medium saucepan, melt butter over medium heat. Add onion; cook until tender, about 2 minutes. Stir in flour, salt and pepper. Cook, stirring constantly, until mixture is bubbly. Remove from heat. Stir in broth and milk. Heat to boiling, stirring constantly. Boil and stir 1 minute. Stir in Chicken and vegetables; remove from heat. Spoon Chicken filling over crust. Place second crust over filling; flute edge. Cut slits in several places. Bake for 35 to 40 minutes or until crust is golden brown