Because I promised, here's how I made the cake in the form of ice cream.
First I made two round cakes 6 inches, a square of 8 inches, and one half of a sphere.
I put my two circular top of each other and cut around to give you a little cone-shaped. After that I covered my cone square and buttercream icing, and then fondant.
If you look, the cone I made fondant lines to make it look more like an ice cream cone. This I did with my rule for fabrics (these transparent) Just be careful not to make very strong the fondant or end up like me cutting the fondant where they want. (if you look closely you will find where my mistake is, but I did not want to repeat all over again just so I left it in the back of the cake where nobody sees it)
Note also that use bamboo sticks again to every level of the cake. This I did after learning the hard way, from first to each separately and second floor it is essential immediately secure, when the top of the cake fell to the ground destroying their step cone. So you will notice that the cone is not exactly perfect in form. The most important piece is the center, because through all the floors of the cake.
After cooking half sphere to replace it it fell, cake looked like this. I decided that the portion of ice cream is going to look better made only in buttercream icing. A few decorations here and there, and this is the result.