Preheat oven to 350°F (175°C).

Pulse Oreo cookies in a food processor or blender until finely crushed.

Transfer crumbs to a bowl, add melted butter, and stir to combine.

Press mixture firmly and evenly into the bottom and sides of a 9-inch pie dish.

Bake for 10–12 minutes. Allow to cool completely.

In a medium saucepan, whisk together the sugar and milk. Cook over medium heat, whisking often, until the mixture reaches a gentle simmer.

In a separate bowl, whisk egg yolks with cornstarch until smooth.

To temper the eggs, slowly add a few spoonfuls of the hot milk mixture into the yolks, whisking constantly. Repeat with several more spoonfuls.

Gradually pour the tempered egg mixture back into the saucepan, whisking constantly. Cook until thickened and just beginning to bubble.

Remove from heat and stir in the butter, chocolate, and vanilla until smooth.

Pour filling into the cooled Oreo crust, smoothing out the top.

Press plastic wrap directly against the surface to prevent a skin from forming.

Refrigerate until fully set, 4–6 hours or overnight.

In a mixing bowl, beat heavy cream on high speed for 1–2 minutes.

Add sugar and vanilla, then continue whipping until soft peaks form (2–3 minutes).

Spread evenly over chilled pie. Garnish with chocolate curls or shavings, if desired.

Serve and enjoy!