Add all cookies into a food processor and chop until in very fine pieces/powder. It should look like sand or dirt.
Melt the butter (in the microwave is fine) and add to the cookie crumbs mixing until all crumbs are coated and begin to stick together.
Cut out a round piece of parchment paper to line the bottom of a 9 inch springform pan and use cooking spray to keep in place. Lightly spray the sides of the pan.
Pour cookie crumbs into the pan, and push them up the sides to create a crust. Try to, as much as possible, keep the crust an even thickness.
Place the crust in the freezer for 5-10 minutes or until cold and set. Then place in the oven for 15 minutes.
While the crust is cooking, melt 1 stick of butter in a saucepan. When the butter is almost completely melted, add the chocolate and sugar and whisk until smooth.
Remove the pot from the heat, and allow the batter to cool slightly. Then add the eggs whisking immediately after cracking them in making sure not to scramble them inadvertently.
Then add the vanilla and cocoa powder, whisking until smooth.
When the 15 minutes are up, take the crust out of the oven. The color will have darkened and it will appear more solid.
Turn the oven up to 365 degrees. Pour the batter into the crust, making sure that spreads evenly. Then place it back in the oven for approximately 25 minutes (or until the cake appears firm. Be careful not to over-bake.
Take the cake out of the oven and leave it to cool.
Pudding and Whipped Cream
Combine the cornstarch (or tapioca powder), sugar, and salt in a small saucepan over low heat.
Slowly, whisk in the milk being careful not to create lumps and continue cooking over medium heat. Cook (stirring occasionally) for about 10 minutes. Longer on lower heat is better than shorter on higher heat.
When the mixture is think enough to coat the back of a spoon, add the chocolate and whisk to incorporate. Continue to whisk as the chocolate melts. At this point, the mixture should be quite thick.
Cook for about another 2-3 minutes, allowing it to simmer slightly. Then add the vanilla, whisking to incorporate into the pudding.
Remove the pudding from the heat, allowing it to cool for a few minutes. If you are concerned about lumps, the mixture can be strained.
When the pudding has cooled to the point that it is slightly warm to the touch, pour it into the crust.
Smooth out the top of the pudding, and cover with plastic wrap. Make sure that the plastic wrap touches the pudding, covering it completely so that a skin does not form.
Place in the refrigerator and allow to cool completely.
While the it is cooling, make the whipped cream.
Pour the heavy cream into a bowl on a stand mixer, making sure that the cream is very cold. Mix at a medium speed until the cream is frothy. Then add the 2TB of sugar and raise the speed to almost all the way (8 out of 10). Watch the cream carefully so that it does not over whip and separate.
At this time, if the pie is not cool, place the cream back into the refrigerator until the pie is completely cold.
When the pie is cold, spoon the whipped cream over the pudding layer, making sure not to create air pockets. Fill until the cream reaches 1 cm below the top of the crust.
Place the pie back into the refrigerator, keeping it there until it is ready to be served.
To remove the pie from the springform pan, carefully loosen the hinge slowly, running a knife around the edge of the chocolate cookie crust as necessary. Do not rush the process, otherwise you may end up with a cookie crumble mess.
Remove the ring of the pan, then slide the pie onto a serving tray or plate.