Prepare the Filling

1. Make the Roux: In a large skillet over medium heat, melt the butter. Once melted, add the flour and stir for 1-2 minutes until it forms a paste.
2. Add Liquids: Gradually whisk in the chicken broth and milk, stirring continuously until the mixture thickens, about 5-7 minutes.
3. Mix in Chicken and Veggies: Stir in the shredded chicken, frozen mixed vegetables, garlic powder, onion powder, salt, and pepper. Cook for another 2-3 minutes, then remove from heat.

Assemble the Pie

1. Prepare the Crust: Preheat your oven to 375°F (190°C). Roll out one pie crust and place it into a 9-inch pie dish.
2. Add Filling: Pour the chicken filling into the pie crust, spreading it evenly.
3. Cut Shapes for Topping: Roll out the second pie crust and use ghost-shaped cookie cutters to cut out ghost shapes. Place the cutouts on top of the filling, arranging them creatively.
4. Egg Wash (Optional): Beat the egg and brush it over the crust for a golden finish.

Bake the Pot Pie

1. Bake: Place the pie in the preheated oven and bake for 30-35 minutes, or until the crust is golden brown and the filling is bubbly.
2. Cool Slightly: Allow the pot pie to cool for a few minutes before serving to let the filling set.