Place the chicken breasts in a pot of water and bring it to a boil. Once boiling, reduce the heat and simmer for 20-25 minutes, or until the chicken is fully cooked. Remove the chicken from the water, let it cool slightly, and shred it. Set aside.

Preheat your oven to 400°F (200°C).

In a large cast iron skillet, melt the butter over medium heat. Add the mirepoix (celery, carrots and onions) and sauté until tender.

Sprinkle the flour over the cooked vegetables and stir to coat them well.

Slowly pour in the chicken broth and heavy cream, stirring constantly until the mixture begins to thicken.

Add in the shredded chicken, frozen peas and carrots, and season with dried parsley, thyme, sage, minced onion, garlic, salt, and pepper. Let the filling simmer for another 5 minutes, stirring occasionally, until it’s heated through and thickened to your preference.

Prepare the homemade pie dough or use store-bought dough. Carefully lay the rolled-out dough over the skillet with the chicken pot pie filling.

Trim any excess dough around the edges with a sharp knife, leaving about an inch to fold over the edge.

Use a sharp knife to make a few small slits or vents in the center of the dough.

For a golden, glossy finish, use a pastry brush to apply an egg wash (1 beaten egg yolk mixed with 1 tablespoon of water) to the top of the dough.

Place the pot pie in the preheated oven and bake for 25-30 minutes, or until the crust is golden brown and the filling is bubbling.

Once done, take the pot pie out of the oven and let it cool for a few minutes before serving.