It’s hard to think of a bigger restaurant success story over the last decade than Shake Shack. The high-end burger chain began as a hot dog cart in 2001 in New York City’s Madison Square Park by famed restaurateur Danny Meyer. The menu was handwritten written by Meyer on a single sheet of paper in about 10 minutes and is about 85 percent the same today.

But there’s so much more to this story. Like for three years after 9/11 that hot dog cart paid the bills at the crown jewel of Meyer’s restaurant empire, Eleven Madison Park. Or how he wasted over a million developing a line of French fries only to throw them away out of pure pride. If Danny Meyer is the heart and soul of Shake Shack, its longtime CEO Randy Garutti is the engine that powers it. Here’s how they built Shake Shack.