Make putting this all-time favorite together a snap by purchasing a ready-to-use pie crust. It does take a little bit of time but my husband loves it.
Rinse canned veggies in cold water; drain. Melt butter in a 2-quart saucepan over medium heat. Stir in flour, onion, 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 for about 1 minute. Stir in chicken and peas and carrots; remove from heat.
Heat oven to 350 degrees.
Make pastry. Roll two-thirds of the pastry into 13-inch square. Ease into ungreased 9x13 square pan. Pour chicken mixture into pastry-lined pan.
Roll remaining pastry into 11-inch square. Cut out designs with 1-inch cookie cutter. Place square over chicken mixture. Arrange cutouts on pastry. Turn edges of pastry under and flute.
Bake about 35 minutes or until golden brown.