Cut shortening into 1 cup flour and salt until particles are size of small peas. Sprinkle in water (1 tablespoon at a time) tossing with fork until all flour is moistened and pastry almost cleans side of bowl. 1 to 2 teaspoons more of water can be added, if necessary.
Gather pastry into ball. Shape into flattened round on lightly floured cloth-covered board. Roll pastry 2 inch larger than inverted 9x1-1/4 inch pie plate. Fold pastry into quarters. Place in plate. Unfold and ease into plate, pressing firmly against bottom and side. Trim edge of pastry 1inch from rim of plate. Fold and roll pastry under, even with plate. Flute.
Preheat oven to 325 degrees F (165 degrees C).
In large bowl, beat eggs until foamy. Add 1/2 cup flour and brown and white sugars. Beat until well-blended. Blend in butter. Stir in chocolate morsels and walnuts. Pour into the pastry-lined pie plate.
Bake at 325 degrees F (165 degrees C) until set, about 1 hour. Serve warm with whipped cream or ice cream. Makes about 8 to 12 servings.