Heat oven 350F.

Cookie Crust

• Mix cookie crumbs and melted butter. Using the back of a teaspoon, press half the crumbs onto the sides of a 9-inch tart pan with removable bottom. Press remaining crumbs over the bottom.
• Place on a cookie sheet and bake for 8 minutes. Cool.

Dark Chocolate Custard Filling

• Whisk sugar, cornstarch and salt in a small saucepan. Add cream, milk, egg yolks and whiskey or vanilla; whisk until well blended.
• Place saucepan over medium heat and cook, whisking constantly until the custard starts to thicken. Stop whisking for a few seconds and check to see if the custard is bubbling indicating it has come to a boil. Whisk another 30 seconds and then remove from heat.
• Stir in chocolate and butter until melted. Use an immersion blender to blend the mixture in the saucepan until it is completely smooth, silky and shiny.
• Pour the custard into the cooled pie shell. Smooth the top. Press a piece of plastic wrap on the surface of the custard to prevent a skin from forming. Chill at least 4 hours or until the custard is cold and set.

Mascarpone Whipped Cream

• In a large bowl, with a hand mixer at low speed, whip the heavy cream, mascarpone, sugar and vanilla until mixed. Gradually increase mixer speed until mixture thickens to medium-soft peaks to dollop or a pipeable consistency for decorating top of pie.

Assemble and Serve

• Remove pie from the refrigerator. Remove plastic wrap.
• Dollop or pipe mascarpone whipped cream over top.
• Press up on the bottom of the tart ring to remove the pie from the fluted sides. Place on a serving plate. Slice into wedges.