Preheat your oven to 350 degrees F. Grease a KitchenAid® Nonstick 9″ Springform Pan and set aside. Combine the Oreos in the bowl of a food processor and pulse until finely ground. Drizzle the melted butter over the mixture and pulse until combined and the mixture looks like wet sand. Press into the bottom of the prepared Springform Pan. Bake the crust until set, about 10-12 minutes. Transfer to a rack and let cool completely.
Meanwhile, in the bowl of a KitchenAid® Stand Mixer, whisk the heavy cream on medium-high speed until soft peaks form. Transfer to a small bowl and refrigerate until ready to use. In a clean bowl, beat the cream cheese, milk and vanilla extract until smooth, about 2-3 minutes on medium speed. Reduce speed to low and add in the powdered sugar and Irish cream. Mix until combined. Using a rubber spatula, gently fold in half of the whipped cream until just incorporated. Continue to fold in the rest of the whipped cream. Spoon the filling onto the crust and smooth the top.