Heat oven to 450 degrees. Lightly spoon flour into measuring cup; level off. In medium bowl, combine flour, brown sugar, cocoa, and salt. Using pastry blender or fork, cut in shortening until mixture resembles coarse crumbs. Sprinkle flour mixture with water, 1 tablespoon at a time, while tossing and mixing lightly with fork. Add water until dough is just moist enough to hold together. Shape dough into ball. Flatten ball; smooth edges. On lightly floured surface, roll ball lightly from center to edge into circle 4 cm larger than inverted 23 cm pie pan. Fold dough in half; place in pie pan. Unfold; fit evenly in pan. Do not stretch. Fold edge under to form standing rim; flute. Prick bottom and sides of crust generously with fork. Bake at 230ºC or 8 to 11 minutes or until crust appears dry and flaky. Cool completely.
In medium saucepan, combine sugar and quarter cup cornstarch. Add milk gradually, stirring over medium heat until mixture boils; boil 1 minute, stirring constantly. Add baking bar and vanilla, stir until baking bar is melted and mixture is smooth. Pour into large bowl; cover top with plastic wrap. Cool to room temperature.
In small bowl, beat whipping cream with powdered sugar until soft peaks form. Beat cooled baking bar mixture at medium speed until light and fluffy, about 1 minute. Fold whipped cream into mixture. Spoon evenly into cooled crust.
Refrigerate 8 hours or overnight until firm.
In small saucepan over medium heat, heat raspberries and 1 tablespoon cornstarch to boiling, stirring constantly. Boil 1 minute, stirring constantly. Cool.
Serve pie with raspberry sauce. Serves 8.