360gramschicken broth, from cooking the chicken and vegetables(1½ cups)
1teaspoonkosher salt(or to taste)
Freshly ground black pepper to taste
1tablespoonflat-leaf parsley, finely chopped
1egg, beaten
Instructions
Crust
Roll out the dough. Place one piece (bottom) in a nine or 10-inch pie plate, and brush with egg wash. Place the second piece (top) on a parchment-lined baking sheet, and refrigerate until needed,
Filling
Put the chicken, potatoes, carrots, celery and onions in a saucepan; cover with the broth. Add the bay leaves, thyme and garlic, and bring to a boil over medium-high heat. Reduce to a simmer for 12 - 15 minutes, until the chicken is just cooked through.
Discard the bay leaves, drain the chicken and vegetables, saving the broth (you will have more than you need for the recipe; save for another use).
Bechamel
Melt the butter in a medium saucepan over medium heat. Whisk in the flour, and cook for 2 to 3 minutes; adjust the heat as needed so that the mixture does not brown. Whisk in the milk and chicken broth, lower the heat to keep the bechamel at a gentle simmer and cook for 10 to 15 minutes, whisking often, until the sauce has thickened and reduced by about ½ cup. Move the whisk over the bottom and into the corners of the pan to be sure the bechamel doesn't burn. Remove from the heat, and season with salt, pepper and parsley.
Assembly
Position the oven racks in the lower third and center of the oven, and preheat the oven to 375 degrees.
Remove both the top and bottom dough from the refrigerator.
Shred or chop up the cooked chicken, then add the chicken and vegetables to the bechamel sauce. Spoon the filling into your bottom crust.
If the top crust is still too hard to shape, let it rest at room temperature for a few minutes.
Moisten the rim of pie shell with some of the beaten egg. Cover the filling with the top crust, and press the edges of the dough together to seal. Trim away the excess dough that is hanging over the rim, or roll it under and crimp it. Brush the top crust with the egg. Cut a small vent (or multiple vents) in the center of the dough with a small cutter or the tip of a paring knife to allow steam to escape.
Bake on a baking sheet on the lower oven rack for 40-50 minutes, until the crust is a rich golden brown. If necessary, move the pie to the center rack during the last 10 minutes of baking to brown the crust. (If the crust is browning too quickly, cover it with aluminum foil.) Transfer to a cooling rack and let rest for 10 -15 minutes before serving.