2 strips bacon
4 tablespoons unsalted butter, plus more for greasing baking dish
2 medium-sized carrots, chopped
2 sticks celery, chopped
1 medium-sized onion, chopped
3 cloves garlic, finely chopped
3 sprigs fresh thyme, leaves only
1 teaspoon red pepper flakes
1 3-1/2 pound roast chicken, meat hand-torn into bite-sized pieces
2 heaped tablespoons of all-purpose flour, plus more for dusting pastry
1 cup chicken stock or recently boiled water
2 cups shredded white cheddar cheese, divided
1 package puff pastry, thawed
1 egg, slightly beaten
Salt and pepper, to taste

Reynolds Wrap® Aluminum Foil