I need help figuring out how to carve a square cake into a pyramid shape for the base of an Eiffel Tower cake. Let me first say  I've never carved a cake ever before, but honeslty looked at this and thought it would not be difficult.

I butchered a practice cake lastnight and feel like im totally over thinking the carving aspect. It can not be rocket science.

Here's a pic of what im ultimately trying to replicate:

http://www.wikihow.com/Make-an-Eiffel-Tower-Cake

I get all the other steps, I just dont understand the physical carving of the cake. I have two 8 x 8 inch squares stacked together and dont know how to get the correct angles from there.

Do I start about an inch in from the edge & cut outwards? That did not give me the trapizoid kinda look I think I should be going for.

Additionally, I want to make the tower out of RKT. Any suggestions for doing that?

You have actually picked one of the most difficult cakes to carve because it is a symetrical structure made of metal .. there is no room for fudging.

My best suggestion would be to make a template for the base .. you will need to work some math magic to figure out how long the bottom is and how long the top is and how long each side will be.  Then start carving away little by little towards where you want to go, checking against the template by laying in on each side until you get where you want to be.  

My other suggestion is to start with a piece of cake that is MUCH larger than your final product.  Because you will inevitably carve too much off one side and need to do the same all around to make them symetrical.  

As for the tower, do the same thing with a RKT.  Make a template and keep checking against it.

Good luck!

(Here is one that I did a few years ago .. lots of lessons learned!  As you can see I didn't give myself enough cake and some sides are not quite the same as others!)