Add the Oreo cookie crumbs and the melted butter to a small bowl and stir to combine.
Press the Oreo cookie mixture into the bottom of a 9-inch spring form pan and set in the refrigerator to chill.
Whip the cream cheese on high speed in a large bowl, adding the powdered sugar slowly until the mixture is creamy and fluffy.
Add the peanut butter and continue beating on high speed until everything is incorporated.
Fold in the whipped cream with a rubber spatula just until combined and pour the cheesecake mixture into the spring form pan on top of the chilled crust.
Smooth out the top carefully with a spatula and allow the cheesecake to set in the freezer for 6 to 12 hours, or overnight for best results.
Make the ganache by heating the whipping cream in a small pot on the stove or in the microwave, removing from the heat just before boiling.
Pour the hot cream over the milk chocolate in a separate bowl and stir gently until the chocolate has melted and the ganache is smooth.
Cool the ganache completely to room temperature before spooning it over the chilled cheesecake.
Store the cheesecake in the refrigerator until serving to be sure the ganache sets and to give the cheesecake a chance to thaw (1-2 hours in the fridge is best)
Just before serving, add some whipped cream and crushed peanuts to the top!