Crust: 2 cups flour, 1/2 t. salt, 1/2 cup finely shredded cheddar cheese, 2/3 cup shortening, 2 T. cold butter, 3 - 4 T. cold water.
Filling: 1 cup diced peeled potatoes, 1/2 cup thinly sliced carrots, 1/3 cup chopped celery, 1/4 cup chopped onion, 1 minced garlic clove, 1 T. butter, 1 cup chicken or turkey broth, 2 T. flour, 1/2 cup milk, 1-1/2 cups cubed cooked turkey, 1/2 cup frozen peas (thawed), 1/2 cup frozen corn (thawed), 1/2 t. salt, 1/4 t. dried tarragon, 1/4 t. pepper.
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. 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 potatoes, carrots, celery, onion, and garlic in butter for 5 - 6 minutes. Add broth; cover and cook for 10 minutes or until vegetables are tender. In a small bowl, 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" 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 edge. Cut slits in top or make decorative cutouts in pastry. Bake at 350 degrees for 35 - 45 minutes or until crust is lightly golden brown. Serve immediately. Yield: 6 - 8 servings.