Preparation / Directions:
Preheat oven to 400 degrees.
For Pastry: Combine flour, butter, and cream cheese in food processor. Pulse on/off several times to form coarse crumbs. Add egg and process until dough forms a ball. Wrap dough in plastic and refrigerate at least 2 hours. (Pastry dough may be made up to three days in advance and kept in the refrigerator, or it may be frozen until ready to use.)
For Filling: Place chicken in a large stock pot. Cover with water, bring to a boil, then lower heat to simmer. Cook until chicken is tender, about 1 hour. Remove chicken from water, cool, remove skins and bones. Cut meat into bite-sized pieces and set aside. Strain the cooking liquid, measure out 2 1/2 cups, and discard the remainder. (Canned chicken stock may be substituted.)
In a large saucepan, melt butter; add onion and celery. Saut‚ over medium heat for 10 minutes. Add flour, salt and pepper. Cook about 5 minutes, stirring constantly to make a roux. Slowly pour in reserved cooking liquid, stirring to make a smooth gravy. Cook until thickened, about 8 minutes. Add chicken, carrots, peas, and thyme. Pour into a deep pie dish or round casserole, about 9 inches in diameter.
On a lightly floured board, roll pastry into a 10-inch round. Using a decorative cookie cutter, cut a shape from the center of pastry round. Lay pastry over the filling, fold edges under and crimp firmly against rim of dish. For decoration, moisten the bottom of the pastry cut-out and place it next to space from which it was cut.
Place pie on a baking sheet and bake on the lowest rack of preheated over for 45 minutes, until pastry is golden brown.
Remove from oven and cool 10 minutes before serving.