Oreo Crust

1. Preheat the oven to 325F.
2. Run the Oreos through a food processor until finely ground. Mix in the melted butter until evenly moistened.
3. Pour it into a 9 inch pie dish and press it into the bottom and up the sides.
4. Bake for 15 minutes.

Chocolate Pudding

1. In a medium saucepan, whisk together the sugar, cornstarch, cocoa powder, espresso powder, and salt.
2. Slowly whisk in the milk until smooth, then whisk in the egg yolks.
3. Place over medium heat and continue to whisk until thickened. This will take about 10 minutes and it will go from liquid to thick very quickly, so keep a close eye on it once it starts to steam.
4. Once thickened, remove from heat and whisk in the chopped chocolate, butter, and vanilla.
5. Pour into the pie crust and spread even. Transfer the pie to the refrigerator while we make the mousse.

Peanut Butter Mousse

1. In the bowl of a stand mixer using the whisk attachment (you can also use a hand mixer, it will just take some extra time and elbow grease), add the cream cheese and mix until smooth.
2. With the mixer running, slowly pour in a small amount of heavy cream. Once smooth, scrape down the bowl and mix in another small amount. Once the cream cheese is thinned out, pour in the remaining heavy cream along with the powdered sugar and vanilla and whip on high speed.
3. Whip until it reaches stiff peaks. Keep a close eye on it as it should reach this point within a minute or two.
4. Scoop half of the whipped cream into a separate bowl.
5. To the whipped cream in the large mixing bowl, add the peanut butter and use a rubber spatula to fold the two together. It will appear somewhat chunky and split at first, but just keep folding and it will smooth out into a glossy mousse.
6. Pile the mousse on top of the chocolate pudding layer and spread even.
7. Plop the remaining whipped cream on top and sprinkle with chopped peanut butter cups.
8. Chill the pie (covered or uncovered) for at least 3 hours or overnight. Then slice and enjoy!