Oops, this is. Actually an "after" picture but here you can see the bowls.
Stack the bowls and hot glue together. Once you have a design in mind, start at the bottom gluing the mini candy bars leaving no space for the bowls to be seen.
Only use a small dab of glue at the bottom and top so you don't Mel the chocolate.
Having a color theme in mind helps the overall look of the cake. Mixing candy bars makes it seem cluttered.
I've used the same bowls for a couple of years now.
For this latest one, I stacked square bowls for a slightly different look.
I punched out circles and glued them to ribbon to make streamers then glued the streamers to the top.