Preheat the oven to 375 degrees F.
*if you are using refrigerated pie crust, make sure to make it out and let it warm up to room temperature while you prepare the rest of the pie. They usually take 15-20 to warm up.
**If you are cooking chicken for this recipe, cook it in the same pan you plan to use for the rest of the pot pie, this will give you lots of yummy added flavor. Fry the chicken breasts in butter and season with salt, pepper, basil, and thyme.
Heat the olive oil and butter in a deep/large cast iron skillet or Dutch oven over medium heat. Once the butter is melted and the mixture is hot, add the onion and garlic, and cook for 2-3 minutes or until fragrant.
Add the carrots and celery, and cook stirring often for 3-5 minutes or until the celery has begun to soften.
Add the peas(I usually use frozen peas) and the cooked chicken. And cook until warmed through.
Next, add the spices and flour, and stir to combine, making sure everything is coated in the seasoning and flour.
Pour in the white wine and whole milk, followed by the chicken stock/broth, and stir to combine.
Bring the pot pie mixture to a simmer, and cook stirring often until thickened, roughly 5-10 minutes. The sauce should be thick enough to coat the back of a spoon.
While the pot pie is thickening, prepare your crust. (see note if using store-bought pie crust.), roll the pie dough out on the lightly floured surface, just until it is big enough to cover the top of the pie. Using your hands gently shape the dough till it matches the shape of your pan. Once the pot pie has thickened, remove the pan from the heat. Then gently pick up your prepared crust and carefully set it over the pie. Do this carefully but quickly to avoid getting burned by the steam! Carefully cut 3-4 slits in the top of the crust with a sharp knife. If you are using an egg wash gently brush it over the top of the crust. Place the pan in the oven and bake for 35-45 minutes or until the top of the crust is golden brown.
Allow the pot pie to cool for 10 minutes before serving.
Enjoy!