Whether you find it to be a taste sensation or to be one of the more vile pairings in fast food's auspicious history, there's little denying that Taco Bell's Doritos Loco Taco has become a food item that transcends the normal boundaries of chain restaurant cuisine. That's no accident, as a new report from Fast Company points out. Turns out Frito Lay and Taco Bell spent nearly three years perfecting the Doritos Loco Taco, and the company considered 30 different alternatives in its quest to reinvent the crunchy taco. We wouldn't have guessed, but there's a lot more into making it than just crafting a taco shell from the same ingredients as Doritos. All the hard work paid off, though — Taco Bell has sold more than 450 million Doritos Loco Tacos since they went national in March of 2012.