Cut the cake in 3 strips. Slice each strip in half, lengthwise, so you have a total of 6 strips
Combine coffee beverage, coffee liqueur and whiskey in a wide bowl
Combine both whipped toppings in a large bowl. Add vanilla and fold until they are both well combined.
Prepare a 6x8x2 glass container. Soak 3 cake strips in coffee mixture and place at the bottom of the container. Top with about ⅔ of the whipped topping mixture. Soak the remaining 3 strips of cake in coffee mixture, place on top and cover with the rest of the whipped topping mixture.
Top with cocoa powder and chocolate shavings
Refrigerate until ready to serve