Preheat the oven to 425° and lightly spray a deep dish pie plate with non-stick cooking spray.
Roll out dough on a lightly floured surface.
Take the pie crusts and place it into the bottom of the prepared pie dish. Set the top pie crust aside temporarily.
In a large frying pan, melt butter over medium heat. Add chicken, onions, celery, and garlic to the pan.
Sprinkle it with Slap Ya Mama seasoning, garlic powder, and pepper. Cook until the chicken is thoroughly cooked and no longer pink, and the onions and celery are tender.
Next, sprinkle flour into the pan, stir and let cook for 2 minutes.
Gradually pour chicken broth and heavy cream into the pan, stirring frequently until hot and thickened.
Next, add the broccoli and cheese. Stir and let cook for 5 minutes.
Spoon pot pie mixture into prepared pie plate and top with remaining pie crust.
Seal and flute edges and cut several slits into the top of the pie crust.
In a small bowl, whisk egg and water together and brush over the pot pie.
Bake for 35-40 minutes or until the crust is golden brown.
Remove from the oven and enjoy!