Roll out the pie dough onto a baking sheet and sprinkle with the pepper, thyme, and sage. Bake at 400 for 8-10 minutes until lightly golden.
Meanwhile, cut the chicken into 1 inch pieces. Heat the oil & butter in a Dutch oven.
Salt & pepper the chicken and toss it into the pot. Let it cook over medium heat for a few minutes, until opaque. While the chicken is cooking, dice the potatoes into 1/2 in pieces. Set aside.
Dice the onion and celery. Scoop the chicken out into a bowl. Toss in the celery and onion and cook them in the liquid in the pot for about 2 minutes.
Stir in the flour. Add in the chicken broth and half & half. Add in the chicken and remaining ingredients.
Bring it to a boil, reduce the heat, and cook on medium heat until the vegetables are just done – about 10 minutes.
Serve the Chicken Pot Pie Soup with the pie crust crumbled over the top.