In a food processor, combine flour and salt; cover and pulse to blend. Add cheese; pulse until fine crumbs form. Add shortening and butter; pulse until coarse crumbs form. While processing, gradually add water until dough forms a ball.
Divide dough in half with one ball slightly larger than the other; wrap in plastic wrap. Refrigerate for 30 minutes.
For filling, in a large saucepan, saute the potatoes, carrots, celery and onion in butter for 5 minutes. Add garlic; cook 1 minute longer. Stir in broth; cover and cook for 10 minutes or until vegetables are tender.
Combine flour and milk until smooth; gradually add to vegetable mixture. Bring to a boil; cook and stir for 2 minutes or until thickened. Add the remaining ingredients; simmer 5 minutes longer.
Roll out larger pastry ball to fit a 9-in. pie plate; transfer to pie plate. Trim pastry even with edge. Pour hot turkey filling into crust. Roll out remaining pastry to fit top of pie; place over filling. Trim, seal and flute edges. Cut slits in top or make decorative cutouts in pastry.
Bake at 350° for 35-45 minutes or until crust is light golden brown. Yield: 6 servings.