In a large skillet, heat butter-style sticks over medium-high heat. Add sliced celery and onion; cook and stir until tender. Add garlic; cook and stir one minute longer.
Step 4: Make the sauce
Stir in flour, salt, thyme and pepper until blended. Gradually stir in broth and almond milk. Bring to a boil, stirring constantly; cook and stir for 2 minutes or until thickened. Stir in vegan chicken, peas, corn and potato-carrot mixture; remove from heat.
Step 5: Assemble the vegan potpie
On a lightly floured surface, roll half of the dough to a 1/8-inch-thick circle; transfer to a 9-inch pie plate. Trim even with the rim. Add filling.
Roll the remaining dough to a 1/8-inch-thick circle. Place over filling. Trim, seal and flute the edge with your fingers or try a more fancy fluting style. Cut slits in the top for the steam to vent.