Crush your Oreo cookies in a plastic bag with a rolling pin or in a food processor. Mix the crumbs and melted butter with a fork in a medium-sized bowl. Press into a 9-inch pie plate and chill until ready to fill.
Melt the baking chocolate in a medium-sized bowl according to the package directions for melting. Typically, chocolate takes about 1-2 minutes on high power; stir every 30 seconds.
Stir half of the can of sweetened condensed milk into the melted chocolate. Add 1 teaspoon of vanilla extract. Let sit for a few minutes, stirring occasionally.
In another bowl, mix remaining condensed milk, peanut butter, and vanilla until smooth.
Whip the heavy cream with powdered sugar and remaining vanilla on high speed until stiff peaks form.
Fold 1 cup of whipped cream into the peanut butter mixture gently. Spread this in the prepared crust.
Carefully fold the remaining whipped cream into the chocolate mixture. Spread over the peanut butter layer.
Top with remaining whipped cream and chocolate shavings. Refrigerate for at least 4 hours before serving.
Notes
For an extra touch, garnish with chopped peanuts or chocolate chips.