In a medium bowl, combine chocolate cookie crumbs and melted butter. Mix until well combined. Press the mixture into the bottom of a 9-inch trifle dish or a large glass bowl to form the crust.

In a separate mixing bowl, beat the softened cream cheese and powdered sugar together until smooth.

In another bowl, whip the heavy cream until stiff peaks form. Gently fold the whipped cream into the cream cheese mixture until fully combined.

Add the Baileys Irish Cream, melted chocolate, and vanilla extract to the cream cheese mixture. Stir until smooth and well blended.

Layer half of the chocolate cheesecake mixture over the crust in the trifle dish. Add a layer of chocolate cookie crumbs, then repeat the layers with the remaining cheesecake mixture and cookie crumbs.

Cover the trifle with plastic wrap and refrigerate for at least 4 hours, or preferably overnight, to allow the flavors to meld.

Before serving, garnish with chocolate shavings or a dusting of cocoa powder.