This looks awesome!

can you please share how did you do it ? 

I can't remember what size cake I baked.....I think it was a 12x18. I baked the cake and then cut it in half lengthwise, filled and stacked. I used melting chocolate wafers for the sides. I melted the chocolate and poured it into a parchment paper lined cookie sheet and placed in the fridge to set. I then measured the sides of the stacked and filled cake to figure out the approximate size size I needed for the length, adding a little more to account for the icing. I think I made the height 4 inches but that will depend on how high your cake is. I did another cookie sheet of chocolate for the ends. I cut the chocolate 'sheets' using a very sharp utility knife and ruler to ensure a straight line. For the icing I used swiss buttercream because it doesnt crust, which means the chocolate sides would stick better. I iced the cake and then stuck the pre-cut chocolate sheets on the outside of the cake to make the box. To make the chocolate pieces stick together, I used melted chocolate for the 'glue' on both the inside and outside seams. To ensure the chocolate box would stay together during transport, I decorated it with fabric ribbon the outside, wrapping it all the way around the chocolate box. The top of the cake is covered with white chocolate shavings. The chocolate bottle I purchased at a local chocolate store. I could only purchase a whole bottle so I used a sharp utility knife to cut it in half. The top foil is just candy wrapping foil I purchased at Michaels and came in handy at hiding the cracked top...lol! The label is a sugar sheet that I purchased from another business. When working with the chocolate, I wore fabric gloves so the chocolate wouldn't melt and leave my fingerprints behind.   The one pictured here was the first one I made. The ones I have made thereafter look much better :)