Chicken Pot Pie Casserole Is High in Protein

Preheat oven to 425°F. Heat 1 tablespoon oil in a large Dutch oven over medium-high heat. Add cubed chicken; cook, stirring often, until no longer pink on the outside, about 8 minutes. Transfer the chicken to a large plate. Do not wipe the pot clean.

Melt ⅓ cup butter in the drippings over medium heat. Whisk in ⅔ cup flour; cook, whisking constantly, until fragrant, about 2 minutes. Gradually whisk in 3½ cups broth; bring to a gentle simmer over medium-high heat, whisking occasionally. Simmer, stirring occasionally, until the sauce is thick enough to coat the back of a spoon, about 6 minutes. Stir in well-drained peas and carrots, well-drained pearl onions, 2 tablespoons thyme (or 1½ teaspoons dried thyme), 2 teaspoons mustard and 2 teaspoons garlic-and-herb seasoning. Simmer, stirring occasionally, for 3 minutes. Remove from the heat; stir in the cooked chicken, ½ cup sour cream, 1 teaspoon salt and ½ teaspoon pepper.

Divide the filling between 2 (8-inch square) freezer- and oven-safe baking dishes. Unfold the 2 thawed puff pastry sheets; cut 3 (2-inch-long) slits in the center of each sheet. Place 1 pastry sheet over each casserole; tuck in any overhanging edges.

To bake immediately: Bake until the filling is bubbling and the pastry is golden brown, 20 to 25 minutes. Let stand for 10 minutes. Garnish with additional thyme, if desired.

To freeze: Let the unbaked casserole(s) cool completely. Coat one side of foil with cooking spray to prevent sticking. Cover with foil (sprayed-side down), then wrap tightly with plastic wrap. Freeze for up to 3 months.

To bake from frozen: Preheat oven to 425°F. (If using glass baking dishes, let the casseroles stand at room temperature while the oven preheats to help prevent thermal shock breaking the dishes.) Remove the plastic wrap and leave the foil in place. Place each frozen casserole on a baking sheet. Bake, covered, until the filling is hot, about 1 hour 20 minutes. Remove the foil and continue baking until the pastry is golden brown, 10 to 15 minutes more. Let stand for 10 minutes. Garnish with additional thyme, if desired.