Preheat the oven to 350 degrees F.
In a large bowl, combine the graham cracker crumbs, sugar and salt. Stir in the melted butter until everything is evenly coated.
Press the mixture firmly into a 9 inch pie dish, making sure the bottom and sides are packed tightly. Bake for 12 to 15 minutes until golden brown. Remove from the oven and let it cool completely.
In a medium saucepan, whisk together the brown sugar, cocoa powder, cornstarch and salt. Add the milk and continue whisking until smooth.
Cook over medium low heat for about 10 minutes until thickened. Bring the mixture to a gentle simmer, reduce the heat to low and cook for 2 more minutes, whisking constantly, until very thick.
Remove from the heat and stir in the dark chocolate, butter and vanilla. Mix until smooth. Pour the pudding into the cooled crust and refrigerate for 2 hours to set.
In a heatproof bowl, whisk together the egg whites, corn syrup and sugar. Set the bowl over a pot of simmering water and whisk for 5 minutes until the sugar dissolves.
Transfer the mixture to a stand mixer and whip on high speed for 5 minutes until stiff peaks form. Add the vanilla and fold to combine.
Carefully mound the meringue onto the chilled pie. Use a kitchen torch to toast the outside of the meringue until golden and toasty. Slice and serve.
