
Preheat oven to 400°F. Whisk egg with 1 tablespoon water. Set aside.
Cook onion in butter over medium low heat until tender, about 5 minutes. Add flour, poultry seasoning, thyme, salt & pepper. Cook 2 minutes more.
Whisk in chicken broth and milk a little bit at a time stirring after each addition. It will seem thick at first but will smooth out. Bring to a boil over medium heat, simmer 1 minute and remove from heat. Stir in turkey and vegetables.
Line a 9" pie plate with one of the crusts. Fill with turkey filling. Brush edges of crust with egg wash and top with second crust. Pinch edges to seal and cut a few slits to vent pie. Brush with egg wash.
Bake 35-40 minutes or until lightly browned and filling is bubbly.
Cool for 10-15 minutes before cutting.