Food is interesting. I usually think about it at around why + 7.
For every natural phenomenon there are different levels of explanation. I like to call these "why" values. For the first value of why, the question "Why is the sky blue?" can be answered with some simple hand-waving about light from the sun passing through our planet's atmosphere. For a value of why + 2 (also known to parents as, "But whyyyyy?") you have to start talking about the fact that light comes in different colors.
Also, I like the idea of cake more than cake itself.