In retrospect, the question shouldn’t be “how did they come up with it?”, but rather “why haven’t taco shells always been made out of Doritos?” Face it, it just makes sense. And that’s probably why Taco Bell has sold 100 million of them in ten weeks, meaning they sold about one per American household in that time. It took McDonald’s 18 years to sell it’s first 100 million burgers. Next up: they’re making a Cool Ranch version.