This is one of my favorite cake designs out now. This cake is covered in buttercream and then pouring a chocolate ganache over the top allowing it to drip down the top of the cake. Then topping it all with candy. This shows you how I accomplished this look using 4 thin layers of cake.
The ganache was made using 2/3 cup of whipping cream. I had 2 cups of melting chocolate. I brought the cream to a boiling temp but didn't let it boil. I removed it from the heat and added the chocolate. I stirred until it was smooth if it's too thick add more cream. Too thin add more chocolate. You want a smooth and pourable but not watery consistency.
Next, your cake must be cold. I keep it in the fridge for at least an hour after I add my final buttercream layer. The cold temperature is was helps the chocolate slow down and harden as it runs down the cake. If not it makes a soupy mess.
Then top it with whatever candy and cookies you want! Have fun with it!
I am more visual learner. If you are like me, take a look at this video here and see how I made it! :)