1 Place 1 1/4 cups flour, 1/2 tsp. salt, 1/2 cup cold butter and 3 Tbsp. water in the bowl fitted with the kneading/crushing blade. Launch the P1 pastry program for 2 minutes 30 seconds. After 2 minutes, add water 1 tsp. at a time if more water is needed for dough to form a ball. Remove pastry from the bowl, wrap in plastic wrap and refrigerate until ready to use.
2. Preheat the oven to 375°F. Spray a 2-quart baking dish with nonstick cooking spray. Thaw the frozen vegetables.
3. Place 1/2 cup flour, chicken broth, thyme, 1/2 tsp. salt and pepper in the bowl fitted with the whisk. Mix at speed 7 for 1 minute. Add 1/3 cup butter and launch the sauce program at speed 4 at 200°F for 8 minutes. Remove the whisk. Stir in the chicken, peas and carrots, onions and mushrooms by hand. Spoon the mixture into the prepared dish.
4. Roll pastry 2-inches larger than top of baking dish. Place pastry over the chicken mixture. Fold over the edge and crimp to baking dish. Cut vents in the pastry to allow steam to escape. Bake for 45-50 minutes or until crust is golden brown.