Preheat oven to 400 degrees F. In a deep 10-inch ovenproof skillet, melt butter over medium-high. Add mirepoix and butternut squash. Cook until softened, stirring often, 6 to 7 minutes.
In skillet, sprinkle vegetables with flour. Cook, stirring constantly, 1 minute. Stir in broth and let mixture come to a simmer. Simmer until mixture thickens, stirring constantly, 1 to 2 minutes. Stir in chicken, milk, kale and sage. Season with salt and pepper. Remove from heat and let cool 10 minutes.
Meanwhile, in a small bowl, whisk together egg and 1 tablespoon water. Dust work surface and a rolling pin with flour. Unroll puff pastry onto surface and roll into a 12" square. Lightly score a 1"-wide crosshatch pattern into dough using a paring knife, taking care not to cut completely through dough. Carefully roll dough onto rolling pin to transfer. Unroll puff pastry over skillet. Puff pastry can hang over edges slightly. Brush evenly with egg wash.
Place skillet on rimmed baking sheet. Transfer to oven and bake until top is golden brown and filling is bubbly, 35 to 40 minutes. Let stand 10 minutes before serving.
Source: Hannaford fresh Magazine, October November 2024