Prepare the Crust:

1. Crush the Oreos: In a medium bowl, combine the finely crushed Oreo cookies and melted butter. Stir the mixture until it has the consistency of wet sand.
2. Set the Crust: Press the Oreo mixture evenly into the bottom of a trifle dish or individual serving glasses. Refrigerate for 30 minutes to allow the crust to set.

Make the Cheesecake Filling:

1. Beat the Cream Cheese: In a large bowl, beat the softened cream cheese and powdered sugar until the mixture is smooth and creamy.
2. Add the Flavors: Add the cocoa powder, vanilla extract, and Baileys Irish Cream to the cream cheese mixture. Continue beating until everything is well combined, and the filling is smooth and fluffy.

Make the Whipped Cream:

1. Whip the Cream: In a chilled bowl, beat the heavy cream with powdered sugar and Baileys Irish Cream until stiff peaks form. This will create a light, airy topping with a hint of Baileys flavor.

Assemble the Trifle:

1. First Layer: Spread half of the Oreo crust into the bottom of the trifle dish or glasses.
2. Cheesecake Layer: Top the crust with half of the Baileys cheesecake filling, spreading it evenly.
3. Whipped Cream Layer: Add half of the whipped cream over the cheesecake layer.
4. Repeat the Layers: Repeat the layers with the remaining Oreo crust, cheesecake filling, and whipped cream.
5. Garnish: Optionally, top with chocolate shavings for an extra touch of elegance and flavor.