Ingredients:

• 1 chicken (3 or 4 pounds)
• 4 cups homemade chicken stock, or canned low-sodium chicken broth, skimmed of fat
• 1 large yellow onion, cut in half
• 2 dried bay leaves
• ½ teaspoon whole black peppercorns
• 1 small bunch fresh thyme
• 2 tablespoons chopped parsley
• zest of 1 lemon
• ½ teaspoon freshly ground black pepper
• 1 rib celery, cut into thirds
• 1 cup plus 5 tablespoons all-purpose flour 
• 2 ¼ teaspoons salt
• 8 tablespoons (1 stick) plus 7 tablespoons unsalted butter
• 2 large egg yolks
• 9 oz. red potatoes, cut into ½ inch pieces
• 2 medium carrots sliced ¼ inch thick
• 6 oz. button mushrooms
• 12 pearl onions, peeled and cut
• 1 medium leek sliced into ¼ inch thick rounds
• 1 cup milk
• 1 tablespoon heavy cream

Directions:

Combine chicken, chicken stock, yellow onion, bay leaves, peppercorns, 3 thyme sprigs, and celery in a stockpot; add enough water just to cover the chicken. Bring the stock to a boil, reduce heat, and simmer uncovered for 1 hour.

Pick enough thyme leaves to make 3 tablespoons. Combine 1 cup flour, ¼ teaspoon salt, and 1 tablespoon thyme leaves in the bowl of a food processor; set remaining 2 tablespoons of thyme aside. Add 10 tablespoons chilled butter, cut into small pieces, and pulse until mixture resembles coarse meal. While the food processor is running, add 3 tablespoons ice water and 1 egg yolk, and process until the dough holds together. Turn dough onto plastic wrap, flatten into circle, and wrap well; refrigerate at least 1 hour.

Drain chicken and reserve the stock. Remove the skin from the chicken and remove all the chicken from the carcass. Shred the chicken into bite-size strips and set aside. Strain the stock and set aside 2 cups. Reserve and refrigerate the remaining stock for another use.

Preheat oven to 375 degrees. Melt the remaining 5 tablespoons of butter in a large sauté pan over medium-high heat. Add red potatoes and pearl onions, stirring occasionally, until the potatoes begin to turn golden, about 4 to 5 minutes. Add leeks, carrots, and mushrooms, and cook 4 to 5 minutes more. Add the remaining 5 tablespoons flour, stirring for 1 minute. Stir in remaining chicken stock and milk, and bring to a simmer. Cook until thick and bubbly, stirring constantly, about 2 to 3 minutes. Add the reserved chicken pieces, parsley, remaining 2 tablespoons of thyme, lemon zest, remaining 2 teaspoons of salt, and the ground pepper. Transfer to a large casserole dish. Set aside.

Roll out the dough until it is ¼ inch thick, and transfer to a baking sheet. Allow to chill 15 minutes.

Make the egg wash: In a small bowl, whisk together the remaining yolk and heavy cream.

Working quickly, place the dough over the top of the chicken mixture, and tuck extra dough around the edges. Cut slits on top to allow steam to escape. Brush with the egg wash, and place on a baking sheet. Bake until crust is golden, about 35 to 40 minutes. Serve hot.

Makes 6 servings.