Combine the flour and salt in a food processor fitted with the metal blade. Add the shortening and butter and process using on/off pulses until the mixture is the size of peas. Add the water 1 tablespoon at a time, processing until the dough just begins to come together.
Form the dough into a ball. Flatten into a disk. Wrap in plastic and refrigerate until chilled, at least 1 hour.
Preheat the oven to 350° F.
Remove the chilled dough from the refrigerator. Let soften slightly if necessary.
Roll out the dough on a lightly floured surface to a 10-inch round, about 1/8-inch thick.
Transfer the dough to a 9-inch pie dish. Crimp the edges decoratively. Line the dough with foil and pie weights or dry beans to keep the crust from bubbling up during baking. Bake until the edges of the crust are lightly browned, about 10 to 15 minutes. Remove the weights and foil and continue to bake for 5 to 7 minutes, until the whole crust is golden brown. Transfer to a rack. Let cool completely.
Pour the milk into a large saucepan and place over low heat. Scrape in the seeds from the vanilla bean, then add the pod, as well. Heat until warm. Stir in 1/4 cup of the sugar and continue to warm until small bubbles form around the edge of the pan, about 5 to 7 minutes.
Using an electric mixer, beat together the flour, cornstarch, eggs and remaining 1/4 cup sugar until smooth. Slowly whisk the warmed milk into the egg mixture.
Return the mixture to the saucepan. Stir over low heat until thick and slightly bubbly, about 10 minutes. Remove from heat. Strain into a large bowl. Add the butter and stir until melted. Press plastic wrap directly onto the surface of the pastry cream. Let cool, then refrigerate until chilled.
Beat together the cream, sugar and vanilla extract in a large bowl until stiff peaks form.
Assembly: Spread a thin layer of pastry cream in the crust. Top with a layer of bananas. Continue to layer bananas and pastry cream until you reach the top of the crust, finishing with the pastry cream to prevent the bananas from turning brown.
Top with the whipped cream and garnish with chocolate shavings.Makes 8 to 10 Source: