• Combine the flour, cocoa powder, salt, confectioners' sugar, and baking powder and stir well.
• Work the butter into the flour mixture, using a pastry blender or fork, your fingers, or a stand mixer. Don't mix the butter in completely; leave some of it in walnut sized lumps.
• Add the 5 tablespoons of water and stir, then add a little more water as needed until the dough holds together when pinched. It should be cohesive, but not sticky. Chunks of butter should still be visible in the mixed dough.
• Shape the dough into a disk, and chill until you're ready to use it. If you aren’t baking right away, freeze the crust and then move it to the fridge to thaw overnight
• Preheat oven to 375. Grease a deep dish pie plate.
• Bring crust to room temperature. On a floured pastry mat, roll it out and lay it over the pie dish. Trim and crimp edges. You may need to stop occasionally and refrigerate the dough, as it will soften while crimping. It needs to stay cold.
• Freeze the crimped and docked crust for 20 minutes to an hour
• Place a piece of parchment paper inside the crust, and fill to the brim with pie weights. Place pie dish on a baking sheet.
• Bake crust for 14-16 minutes at 375. Remove pie weights, then bake crust for 7-10 minutes more, without the pie weights. Let par-baked crust cool.

Pie Filling

• Reduce oven heat to 350.
• In a mixing bowl, beat egg whites and baking powder until soft peaks form. Add cream of tartar, beating constantly. Add 1 cup of sugar, 1-2 tablespoons at a time, beating constantly until stiff peaks form. Beat in vanilla. Using a rubber scraper, fold in graham crackers, chocolate chips, and nuts. Pour mixture into par-baked crust and bake for 30 minutes.
• Let cool completely on a wire rack. The pie will sink a bit as it cools.
• Prepare topping. In a chilled bowl, using chilled beaters, beat cream until it begins to thicken. Add sugar and vanilla and continue beating until stiff peaks form. Do not overbeat. Top pie with whipped cream. Garnish with extra hazelnuts and chocolate if desired.