The world's biggest fast food chain is no longer McDonald's

McDonald's has had the most fast food chain outlets around the world - but not anymore. It is now being surpassed by Mixue Bingcheng. That's Chinese for Honey Snow Ice City." This chain is exploding across Asia. It became a public company this month, joining Hong Kong's stock exchange to great fanfare. Mixue's growth shows no signs of stopping and there is now speculation it will be coming to North America. What's the secret to Mixue's domination? The World's Patrick Winn reports.