Preheat the oven to 425˚F.
In a large skillet on medium heat, add butter, onions, and carrots. Cook until the carrots are tender, about 8 minutes.
Add in the garlic and sauté for 1 minute then mix in the flour. Cook the flour for a few minutes then add in the chicken stock, heavy cream, salt, and pepper. Simmer for a few minutes until a thick sauce forms.
Turn off the heat and mix in turkey, peas, and parsley.
Roll one pie crust into a 12" circle and transfer it to a 9" pie dish.
Place the turkey pot pie filling over the crust.
Roll the second pie dough into a 10" circle and place it over the filling. Fold the excess dough behind the bottom crust and seal the edges together. Cut slits on top of the pie crust to allow steam to escape.
Beat an egg and brush it over the crust.
Bake for 30-35 minutes until the crust is golden brown. Let the pot pie rest for 15 minutes before slicing.