In medium bowl, mix 1 cup flour and the salt. Cut in shortening, using pastry blender (or pulling 2 table knives through ingredients in opposite directions), until particles are size of small peas. Sprinkle with cold 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 water can be added if necessary).
Gather pastry into a ball. On lightly floured surface, shape pastry into flattened disk. Wrap in plastic wrap; refrigerate about 45 minutes or until dough is firm and cold, yet pliable. (If refrigerated longer, let dough soften slightly before rolling.)
Heat oven to 425°F. On lightly floured surface, roll pastry with floured rolling pin into round 2 inches larger than upside-down 9-inch glass pie plate. Fold pastry into quarters; place in pie plate. Unfold and ease into plate, pressing firmly against bottom and side. Trim overhanging edge of pastry 1 inch from rim of plate. Fold and roll pastry under, even with plate; press edge with tines of fork or flute if desired.
Place peaches in pastry-lined plate. Mix granulated sugar and 1/2 teaspoon nutmeg; sprinkle over peaches. In small bowl, beat whipping cream and egg with fork or wire whisk until blended; pour over peaches. In another small bowl, mix topping ingredients with fork until crumbly; sprinkle over peaches.
Cover edge of pastry with 2- to 3-inch-wide strip of foil to prevent excessive browning; remove foil for last 15 minutes of baking. Bake 35 to 40 minutes or until top is golden brown. Cool 30 minutes. Serve warm.