Easy Chicken Pot Pie

1 (397 g) package puff pastry, thawed and rolled for top
1/4 cup butter
1 medium onion, chopped
1/4 cup all-purpose flour
1/2 teaspoon poultry seasoning
salt and pepper, to taste
1 cup chicken broth
3/4 cup light cream or 3/4 cup milk
2 3/4 cups cooked chicken (cut up) or 2 3/4 cups cooked turkey (cut up)
1 1/2 cups mixed vegetables
Directions:

1
Thaw pastry according to package directions.
2
Heat butter in large saucepan. Cook onion in butter until tender-crisp.
3
Add flour and seasonings, mixing until smooth.
4
Gradually stir in broth and milk. Cook, stirring constantly, over medium heat until mixture comes to a boil and is smoothly thickened.
5
Stir in chicken and vegetables.
6
Cool slightly. Spoon into baking dish.
7
Place rolled out puff pastry on top and make slits for steam to escape.
8
You can brush with egg white. (opt.).
9
Bake on lower rack in oven @ 375*F. until filling is bubbling and crust is puffed and golden brown. 30-35 minutes.