Melt butter in the microwave and let it cool down slightly while preparing the Oreo crumbs.
Blitz Oreos into crumbs using a food processor or by placing the cookies into a ziplock bag and crushing them with a rolling pin. Mix the crumbs with the warm butter and a pinch of salt until it all comes together.
Line an 8-inch pie tin with the Oreo crust mixture and press it flat evenly using the back of a spoon. Once the crust is evenly distributed and pressed tightly into the pie tin, place it into the freezer to set it whilst preparing the filling.
Make the peanut butter filling
Whip the cream cheese and the powdered sugar with an Electric hand mixer for a few minutes until light and fluffy, but do not overwhip.
Fold the peanut butter into the whipped cream cheese mixture using a rubber spatula.
In a separate bowl, whip cold heavy cream until soft peaks form, but do not overbeat, or it can go stiff, and then it will break.
Now gently fold the whipped heavy cream into the peanut butter cream cheese mixture. It must stay light and fluffy before pouring into the crust.
Pour the peanut butter pie filling into the Oreo crust and smooth the top with an Offset spatula. Place it into the fridge and let it set for a minimum of 4 hours.
Before serving, make the decorations by whipping heavy cream and cream cheese until it increases in volume and reaches a pipeable consistency. Fold in the crushed Oreo crumbs and pipe a decoration on top of the pie using a French star nozzle tip.
Any leftovers can be stored covered in the refrigerator for 2-3 days.
Notes
Ingredient notes
Weigh all ingredients by the gram using a digital scale for precision.
Make sure the heavy cream is very cold and has a fat content of at least 36%.
Use full-fat cream cheese and smooth, unsweetened peanut butter.
Technique notes
Whether using the food processor or rolling pin method, make sure that the crumbs are super fine.
When melting the butter, make sure that you do not overheat it. It needs to cool slightly before mixing it with the cookie crumbs.
The butter acts as a binding agent in this recipe. Once it is cooled in the fridge, it will set. You may have had a bad experience in the past with Oreo crust being too crumbly and not holding its shape. This was likely due to not using enough butter in the recipe.
The one and only secret to making a firm, neat crust is to press the crumbs firmly and evenly into the side and the bottom of your pie tin. A spoon with a bent handle is probably the best tool for this step.
Because butter softens at room temperature, it is not recommended to keep this crust out of the fridge for longer than 20 minutes, or the crust will start to "melt".
Do not overwhip the cream filling, or it can go runny.
The 4 hours of chilling time in the fridge is important for the no-bake pie filling to set properly, so don't skip or shorten this step.