Place the whole chicken into a large Dutch oven. Pour in the water, add 1 tsp salt, 0.5 tsp pepper, the celery, onion, and bay leaf. Bring it to a gentle boil.

Cover it up, lower the heat, and let it simmer for about an hour until the chicken is perfectly tender.

Once cooked, remove the chicken from the pot and let it cool. Discard the bay leaf and veggies.

When cool enough, remove the skin and bones, then cut the meat into bite-sized pieces.

Skim any fat that floats on the broth. Bring it back to a boil and add the frozen veggies and cubed potatoes.

After it returns to a boil, reduce the heat, cover, and let it simmer for about 8 minutes until the potatoes are tender.

Remove the good stuff with a slotted spoon and set it aside. Measure out 3 cups of the broth and reserve it.

In your Dutch oven over low heat, melt the butter. Stir in the flour, whisking for about a minute to create a roux.

Gradually add the reserved broth and milk, stirring constantly as it thickens and bubbles.

Stir in 1.5 tsp salt, 1.25 tsp pepper, and thyme. Add the chicken, cooked veggies, and potatoes, and gently combine.

Preheat your oven to 400°F. Pour the filling into a greased 9x13 inch baking dish.

Roll out your pie crust on a floured surface until it’s about the size of a 15 by 11 inch rectangle. Cover the filling and crimp the edges tightly.

Cut several slits in the top for steam to escape.

Bake for 20-25 minutes until the crust is golden brown and the filling is bubbling.

Let it cool for about 10 minutes before serving.