Who exactly was the first person to realize that one could pluck an unfertilized egg from beneath a hen, crack it and spill its contents into a hot pan and eat it? What was the context where the event took place? It wouldn't appear to be starvation, as one might imagine the person would have just eaten the chicken, unless of course it was a starving person with such tremendous foresight as to first test his curiosity before proceeding with the chicken slaughter. How surprised was that person when he or she first ate it and found fried eggs are delicious and go well with ketchup, soy sauce and, above all else, a delightful combination of Hollandaise sauce, Canadian bacon and English muffins?
These questions have no answers, of course, and hence no real purpose aside from priming the imagination. Which makes them kind of dumb at their foundation; rhetorical is another way to put it. They produce nothing beyond a shrug. It's not like the origin question concerning chicken or the egg, which, as it turns out, has been definitively answered by the founder of this site.
There is some validity to investigating what happened because of the cooking of that first egg, I recently found. In an interview in New Scientist with anthropologist Richard Wrangham proposes that cooking is what kicked human divergence from our primate cousins into hyperdrive. Unfortunately, we don't have any better grasp on the events surrounding the first cooked food than we do that first egg. Wrangham says anthropologists reckon it took place some time in the vast gulf of time between one million and 50,000 years ago.
Wrangham wrote a book last summer (here's the NYT review) which introduced a new idea of how humans evolved, the cooking hypothesis. It makes sense; cooking food releases more nutrients for absorption than eating raw food, which allows for more energy gained from less food. This alone would give us a competitive edge, since it makes us healthier (reproductively and otherwise) and reduces time spent foraging and hunting.
The cooking hypothesis also lends itself to social development as well. Cooking takes place around a fire, which tends to generate group congregation, hence socialization. Wrangham also takes it a bit further, positing that the female-subservient role of cooking for males evolved as a need for protection. Since cooking takes longer than eating food as it is foraged, the food is left vulnerable to potential thieves. Wrangham says that males evolved to strongarm anyone who came a lookin to see what was cookin while the females worked the food.
Really, Wrangham's hypothesis is fraught with all manner of implications -- from accounting for the male/female dynamic to the expansion of our brain size to the domestication of animals. And it makes utter and complete sense. As he put it, "What is extraordinary about this simple claim is that it's new."