While fast food was still hugely popular, in the 2000s customers were becoming more health conscious. Shake Shack emphasized its use of fresh, hormone and antibiotic-free Angus beef from the outset, making the brand perfect for the decade. It started as a hot dog and hamburger cart in Madison Square Park, New York City in 2001 (pictured), and by 2004 had become a permanent fixture.

Demand has remained high ever since; in 2010, Shake Shack had locations throughout New York, as well as in Miami, Florida. Today, there are more than 500 branches around the world, with further plans to open 1,500 more in the near future.

Now check out the vintage photos that show where America's most famous food companies started

Last updated by Emily Shardlow-Price.

The fast food everyone was eating the decade you were born