Chicken Pot Pie

1 pkg (10 ounce) Frozen peas and carrots
2/3 c butter
2/3 c flour
1/3 c chopped onion
1/2 tsp Salt
1/4 tsp pepper
1 3/4 c chicken broth
2/3 c milk
2 1/2-3 c chicken cubed or shredded
2 9 inch pie crust

Rinse frozen peas and carrots under running cold water to separate, drain. Heat butter over low heat until melted. Stir in flour, onion, salt, and pepper. Cook, stirring constantly until mixture is bubbly; remove from heat. Stir in milk and broth. Heat to boiling, stirring constantly. Boil and stir 1 minute. Stir in Chicken and vegetables. Put pie crust in a 9" pie pan, pour filling in, place top crust on and flute edges. Bake at 425 degrees for 35 minutes.