This savory favorite is easier than ever to make thanks to the roasted chicken and chopped vegetables available in most markets. The recipe can be made in individual pie pans or bowls as well, though you may need to prepare a double recipe of dough to ensure you have enough to top each serving. Don’t substitute dried herbs here-they won’t give you the dynamic flavor that fresh ones offer.

Transfer the circle of pie or tart dough to a baking sheet and chill until ready to use.

Melt the butter over medium heat in the saucepan. Add the onion and celery and cook, stirring occasionally with the spatula, for 5 to 7 minutes, until softened. Remove the pan from the heat and whisk in the flour. Whisk vigorously to blend the flour with the vegetables and butter. Return to the heat and cook, whisking, for 2 to 3 minutes (do not let the flour brown). Remove the pan from the heat. Add about 1 cup of the stock and whisk until the mixture is smooth and pastelike. This is your only chance to remove any lumps of flour, so whisk thoroughly. Once the paste is smooth, whisk in the remaining stock. Return the pan to the heat and bring to a boil, whisking frequently. Add the carrots. Reduce the heat and simmer for 5 minutes. Remove from the heat.

Fill the large bowl halfway with ice and water and set it aside. Heat the olive oil in the sauté pan over high heat. Add the mushrooms and cook, stirring every 2 to 3 minutes, until deep golden brown, 10 to 12 minutes. Add the mushrooms to the filling along with the chicken, peas, chives, parsley, and thyme. Season to taste with salt and pepper. Set the saucepan into the bowl of ice water. Stir occasionally until the filling is cool. (Chilling the filling prevents the flaky pastry from melting when it's placed on top of the pie.) Scrape the filling into the pie pan.

Preheat the oven to 375°F and position an oven rack in the center. Brush the edge of the pie pan with a thin film of water. Transfer the dough to the pan, roll the edges to form a thick rope along the edge of the pan, then crimp or form a decorative border as desired. Any leftover pie dough can be used to make decorative designs, such as a chicken, on top of the pie crust. In a small bowl, beat the egg yolk with the milk or cream and use the pastry brush to lightly glaze the surface of the pie. 5 Bake for 40 to 45 minutes, until the filling is bubbling and the crust is golden brown and crisp. Transfer to a rack and let cool for 15 to 20 minutes. Serve hot, spooning filling and crust into wide, shallow bowls.

Storing: Any leftovers may be covered with plastic wrap and refrigerated for up to 4 days. Reheat in a 375°F oven for 15 to 20 minutes before serving.