If you need to cook the chicken still, you’ll need to do that first, let it cool, then shred it. Also, set the cream cheese and pie crusts out to come to room temperature before you begin, shred the cheese, and preheat your oven to 400°F
In a large skillet over medium heat, add the cream cheese and chicken. Stir until the cheese is melted and well combined with the chicken. Pour in the Buffalo sauce and stir in the cheddar cheese. Cook a minute or two until everything is melted and blended.
Take your pie crusts and cut them in half, then in half again, so you have 8 pieces total.
Divide the chicken mixture evenly among the 8 pieces of pie crust, keeping it to one side with about 1/4-inch border along the edges. Wet the edges of the pie crust with a little water, fold over, and seal all along the edges with the tines of a fork.
Cut two small slits to vent, brush with egg wash (optional), and place on a baking sheet. I always line mine with Silpat mats to prevent sticking.
Bake for 17-20 minutes, until the crust is golden brown. Let them cool a few minutes before attempting to eat them - trust me!