Preheat the oven to 375°F. Spray a 9-inch pie plate with nonstick cooking spray.
For the crust:
In the bowl of a food processor combine the graham crackers, sugar, cinnamon, and salt. Pulse until the crackers are finely ground. Add the butter and pulse until mixture is moistened. Press into the bottom and up the sides of the prepared pie plate. Bake for 9 minutes, or until toasted and fragrant. Let cool completely on a wire rack.
For the filling:
In a large bowl whisk together the sugar, cornstarch, cocoa powder, espresso powder, salt, red pepper (if using), egg, and egg yolk. Place the milk in a medium saucepan over medium-high heat and cook until tiny bubbles form around the edges of the milk and it reaches 180°F. Do not boil.
Gradually whisk half of the hot milk mixture into the egg mixture, whisking constantly. Return the milk-egg mixture to the saucepan and cook over medium heat for 10 minutes, or until thick and bubbly, stirring constantly. Remove from heat and stir in the chocolate.
Place the pan in a large ice-filled bowl for 10 minutes, stirring often, until the mixture has cooled. Spread mixture into the cooled crust, cover the surface with plastic wrap, and chill for at least 3 hours, or until set.
For the topping:
In a clean bowl beat the cream on high speed. Slowly add the sugar, cinnamon, and vanilla and beat until stiff peaks form. Spread or pipe onto chilled pie just before serving.