Once upon a time, the great god Xocolatl was bored. The party was over, there was a mess in the divine mansion, and nothing was left besides savory snacks and stale beer. Now Xocolatl was a cool god, but he hated being bored and having to clean up after his hosts, so he decided to make something instead, while waiting for the heavenly servants to tidy up.
Xocolatl retired to his Place of Making, and began to mix ingredients. He had sweet things, sour things, savory things (from the party leftovers – Xocolatl was a thrifty deity apart from the mansions and servants) and salty things (also from the party). He mixed them together in a Magic Ratio and they became something he had never had before. It was magical and divine, and since these attributes were of great interest to him, being as he is magical and divine also, he decided he’d make an entire universe in which this substance could become.
Unfortunately, gods are subject to laws, and the laws of existence meant that he could not simply make a universe of this magic and divine ingredient ex nihilo. He had to have this substance, which he named after himself, xocolatl, as the end product of mixing the four substances that comprised it, and which it was more than the sum of. In short, he needed a universe that had as its end and goal, the production of xocolatl.
So he sighed at the wasted space, physics and time, and just got on with it. He made the stars, the galaxies, the nebulae and all the physical processes that produced xocolatl factories, which those who came later called planets. On each xocolatl factory, Xocolatl supervised the evolution of beings that could refine and enjoy the divine and magical substance. The fifth substance was not only the purpose of the universe, but gave these beings their own purposes, morals, standards and rules. Xocolatl had made a moral universe by accident!
Moreover, watching the antics of these beings was a great cure for boredom, he thought as he nibbled on some of his namesake. He then put that on his Book of Face.