1. In a food processor or bowl, combine flour, 2 tablespoons granulated sugar, and butter. Whirl or rub with your fingers until the mixture is crumbly. Whirl until the dough forms a ball, or press dough firmly into a ball. Press dough evenly over bottom and 1 inch up the side of a 9-inch cake pan with a removable rim.
2. Bake crust in a 350° oven until golden, about 18 minutes. Cool on a rack.
3. Meanwhile, in a 1- to 2-quart pan, mix 6 tablespoons water, 1/3 cup granulated sugar, and 1/2 cup raspberries. Bring to a boil over medium heat, stirring.
4. Blend the cornstarch with 2 tablespoons water and mix with the berries in the pan. Stir until boiling. Cool, stirring occasionally. If making ahead, cover and chill up to 4 hours.
5. Up to 1 hour before serving, spread the cool raspberry sauce over bottom of baked crust. Mound remaining berries on sauce.
6. Whip cream until soft peaks form. Stir in grated orange peel and powdered sugar. Mound whipping cream onto berries.