In a medium pan or Dutch oven, melt butter over medium heat. Add bacon and cook, stirring occasionally, until crispy and golden brown, 5 to 7 minutes.
In a medium bowl, combine chicken, flour, salt, black pepper, and red pepper; toss until well coated. Add to pan and cook, stirring occasionally, until browned on all sides, 7 to 10 minutes. Add mushrooms, leeks, carrot, parsnip, celery, garlic, and thyme. Cook until vegetables are softened, 10 to 15 minutes. Stir in sherry, scraping browned bits from bottom of pan with a wooden spoon. Cook, stirring occasionally, until reduced, 3 to 5 minutes. Stir in chicken broth. Bring to a boil over medium-high heat; reduce to a simmer and cook, stirring occasionally, until chicken is tender and broth is thickened, 20 to 25 minutes. Let cool for 15 minutes.
Preheat oven to 400º. Line a rimmed baking sheet with parchment paper.
On a lightly floured surface, roll half of All Butter Pie Dough to a ⅛-inch thickness. Using a 4¾-inch cutter dipped in flour, cut 12 rounds from dough. Wrap scraps in plastic. Fit dough rounds into 12 (3¾-inch) mini pie dishes. Brush edges with beaten egg. Spoon chicken mixture into crusts.
On a lightly floured surface, roll remaining half of dough to a ⅛-inch thickness. Using a 3½-inch cutter dipped in flour, cut 12 rounds from dough. Add scraps to previous scraps. Using a ½-inch round cutter or piping tip dipped in flour, punch a circle from the center of each round. Brush bottom of rounds with beaten egg, and place 1 round with cut out on top of each dish, pressing to adhere dough rounds. Place dishes on prepared pan.
On a lightly floured surface, roll reserved dough scraps to a ⅛-inch thickness. Use desired strips of dough to make flowers. Brush bottoms of dough with beaten egg and place on top of pies, pressing gently to adhere. Freeze until firm, about 15 minutes.
Bake until golden brown and bubbly in centers, 20 to 25 minutes. Let cool for 10 minutes before serving.
Recipe by Victoria at https://victoriamag.com/miniature-meat-pies/