Guest post: how to make a dinosaur cake

Today's post comes from my preschool son, who is currently busy planning his upcoming birthday party.  In his mind, this will be a major extravaganza, the most important element of which is an elaborate dinosaur cake.  I can bake a cake, but I am not a cake decorator.  I thought I had come up with a compromise when he agreed to a cake with dinosaurs posed on top.  I was envisioning little plastic dinosaurs perched atop chocolate cupcakes when he wandered back into the kitchen to double check something: "Mommy, not toy dinosaurs, though.  Dinosaurs made of frosting."  Agh!  I was so close!  Unfortunately I do not know how to make a dinosaur out of frosting, so while I was spending some quality time with Google and the "how to make a dinosaur cake" search findings, he decided to spare me and draw out his concept cake.

Here's what he wants:

As I studied this drawing trying to imagine how to create this impossible cake, he again took mercy on me and decided to write out the recipe.  Here it is, in case you want to make a similar cake of your own:

Can't read the directions?  I've annotated the recipe below:

See?  How hard can it be?