Preheat your oven to 400°F (200°C).
In a large saucepan, combine the shredded chicken, mixed vegetables, flour, and thyme over medium heat.
Gradually stir in the chicken broth and heavy cream, then bring the mix to a boil.
Reduce heat and let the mixture simmer until thickened, about 5–7 minutes.
Season with salt and pepper to taste, then remove from heat.
Transfer the chicken and vegetable mixture to a greased casserole dish.
Cover the mixture with the refrigerated pie crust, sealing the edges.
Cut slits into the top of the crust to allow steam to escape.
Bake in the preheated oven for 25–30 minutes or until the crust is golden brown.
Let the casserole cool for a few minutes before serving.