1. Prepare the pie crust. Make a double batch of Authentic Foods Flaky Gluten-Free Pie Crust according to the linked recipe. Prepare the dough as directed and keep it chilled while making the filling.
2. Cook the vegetables. Melt the butter in a large skillet over medium heat. Add the onion, garlic, carrots, and celery. Cook for about 5–7 minutes, stirring occasionally, until the vegetables begin to soften.
3. Add the flour. Sprinkle the Steve’s Cake Flour Blend over the vegetables and stir to coat evenly. Cook for about 1 minute.
4. Make the gravy. Gradually pour in the chicken broth, stirring constantly to prevent lumps. Continue cooking until the sauce thickens.
5. Finish the filling. Stir in the shredded chicken, peas, salt, black pepper, and thyme. Remove from the heat and allow the filling to cool slightly before assembling the pie.
6. Assemble the pie. Preheat the oven to 375°F (190°C). Roll out half the chilled dough and fit it into a pie dish. Add the filling, spreading it evenly. Roll out the remaining dough and place it over the filling.
7. Seal and vent. Trim any excess dough, crimp the edges to seal, and cut several slits in the top crust to allow steam to escape. Brush the top with egg wash.
8. Bake. Bake for 30–35 minutes, or until the crust is golden brown and the filling is bubbling. If the edges brown too quickly, cover them loosely with foil.
9. Rest and serve. Let the pot pie rest for 10–15 minutes before slicing so the filling can settle.

Make-Ahead Tip: Prepare the filling in advance and refrigerate it until ready to assemble. For the best crust, let the filling cool before adding it to the pastry.

Freezing Tip: For the best results, assemble the pot pie in a freezer-safe pie dish and freeze before baking. When ready to bake, follow a tested frozen-pie baking method, allowing additional time as needed. Make sure the center reaches a safe temperature before serving.