Crush the chocolate sandwich cookies using a food processor or by placing them in a ziplock bag and rolling with a rolling pin. Combine the crumbs with melted unsalted butter. Press this mixture firmly into the bottom of a baking dish and chill for about 10 minutes until set.

Beat the softened cream cheese with powdered sugar and cocoa powder in a mixing bowl until smooth and creamy. Fold in the whipped topping gently until everything is well combined, creating a light and fluffy mixture.

Spread the cocoa cream layer evenly over the chilled cookie crust, smoothing it out with a spatula to ensure it covers the base completely.

Prepare the pudding according to package instructions using cold milk, whisking until it's thick and creamy. Spread this pudding layer over the cocoa cream layer, leveling it out so it looks even and inviting.

Top with a generous layer of whipped topping, then scatter marshmallows and chocolate shavings or chips on top for added texture and a dazzling appearance.

Chill the entire dessert in the refrigerator for at least 4 hours (or overnight) to allow the layers to set perfectly before slicing into decadent pieces.