Chicken Pot Pie with Flaky Crust

Why I Love This Recipe
One of the best chicken pot pies I had was at Lady and Sons in Savannah Georgia. I love Paula Deen, so when I saw this recipe I thought of her version of it.
Ingredients You'll Need
1 sheet frozen puff pastry (thawed)
1 T. olive oil
1 lb. boneless, skinless chicken breast, cut into 1/2 in. pieces
1 large onion coarsely chopped (1 cup)
1 cup baby carrots (quartered)
3/4 cup frozen sweet peas
1/2 cup sour cream
1 jar (12oz.) chicken gravy
2 T. cornstarch
1/4 tsp. dried thyme leaves
1/4 tsp. pepper
1 egg (beaten)
Directions
Heat oven to 350 degrees. On lightly floured surface, unroll puff pastry.
Roll to 11 inches square. Cut off corners to make 11 in. round.
Cut slits or small designs in several places. Set aside.
In skillet, heat oil. Pat chicken dry with paper towels, add to pan, cook about 4 minutes stirring frequently, until no longer pink inside.
Add onion and carrots; cook and stir 5 minutes or till crisp tender. Remove from heat and stir in peas.
In medium bowl, beat remaining ingredients EXCEPT EGG with wire whisk til blended. Stir in chicken mixture in skillet.
Spoon into 9 in. deep dish glass pie plate (Spray first with cooking spray)
Place pastry over filling, allowing to hang over the edge just a little.
Place dish on a cookie sheet and bake for 20 minutes. Brush crust with beaten egg. Cover edge of crust with foil to prevent excessive browning.
Bake 20 to 25 minutes longer or until crust is golden brown
Let stand 10 minutes before serving.