Instructions

• Preheat the oven to 400°F. Lightly grease a 9×9-inch square baking dish and set it aside.
• In a large skillet over medium heat, melt 1/3 cup butter.
• Add 4 cups diced assorted vegetables to the skillet and sauté, stirring occasionally, until crisp-tender, about 5 minutes.
• Sprinkle in 1/2 cup flour, 1/2 teaspoon sea salt, 1/2 teaspoon garlic powder, and 1/2 teaspoon onion powder. Stir to coat the vegetables and cook, stirring constantly, for 1 minute.
• Gradually pour in 1 1/2 cups chicken broth and 1 1/2 cups half-and-half, stirring constantly. Cook over medium heat until the mixture thickens and becomes bubbly.
• Stir in 1 1/2 cups shredded rotisserie chicken. Taste and, if needed, add more salt to suit your preference.
• Pour the hot filling into the prepared 9×9-inch baking dish and spread it into an even layer.
• Unfold 1 sheet thawed puff pastry onto a lightly floured surface. Gently press together any seams and, if necessary, roll to size so the pastry will fully cover the baking dish.
• Place the puff pastry sheet over the filling. Trim any excess pastry so it fits the dish, and press the edges to seal (tuck or crimp the edges as desired).
• In a small bowl, whisk together 1 egg and 2 tablespoons water. Brush the egg wash evenly over the top of the puff pastry.
• Use a sharp knife to cut several small slits in the puff pastry to vent steam.
• Bake in the preheated 400°F oven for about 30 minutes, or until the puff pastry is golden brown and the filling is bubbly.
• Remove from the oven and let the casserole rest for 5–10 minutes before serving.