Preheat oven to 425°. Place potatoes and carrots in a large saucepan; add water to cover. Bring to a boil. Reduce heat; cook, covered, 8-10 minutes or until crisp-tender; drain.
In a large skillet, heat butter over medium-high heat. Add onion; cook and stir until tender. Stir in flour and seasonings until blended. Gradually stir in broth and milk. Bring to a boil, stirring constantly; cook and stir 2 minutes or until thickened. Stir in chicken, peas, corn and potato-carrot mixture; remove from heat.
Unroll a pie crust into each of two 9-in. pie plates; trim crusts even with rims of plates. Add chicken mixture. Unroll remaining crusts; place over filling. Trim, seal and flute edges. Cut slits in tops.
Bake 35-40 minutes or until crust is lightly browned. Let stand 15 minutes before cutting.