Shake Shack Surges in Trading Debut

Hamburger chain Shake Shack spiked more than 130 percent in its trading debut Friday after pricing at $21 a share. 

The company is trading under the ticker symbol "SHAK" on the New York Stock Exchange. The stock opened at $47 per share.

Restaurateur Danny Meyer first opened Shake Shack in 2001 out of a hot dog cart in a New York City park.

"We didn't have any dreams that today would ever come," he told CNBC after the stock priced. "We wanted to open a hot dog cart to help a park in Madison Square Park. And when you put a great product together with amazing people with the kind of heart that you have felt here on the floor, these people are doing it, and it's our staff that this day is for."

The chain has 63 locations within the U.S. and internationally. In the fiscal year ending Dec. 25, 2013, Shake Shack's revenue totaled $82.5 million, a $25 million revenue gain since the 2012 fiscal year, according to an SEC filing.

Today's trading values Shake Shack at more than $1 billion.

Asked whether the valuation put considerable pressure on the chain, Meyer said, "We cook one burger at a time with one smile at a time, and I don't know how you value that."

While sales at comparable stores have slowed, future growth will come from restaurant expansion, Randy Garutti, Shake Shack CEO, told "Squawk on the Street."

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