Shares of Shake Shack, a burger chain that began from a New York City hot dog cart, has more than doubled its market share on its very first day of trading.

The company had raised $105 million for an initial public offering (IPO) on Thursday, with 5 million shares going at $21 apiece with forecasts that it would get about $14 to $16 per share from investors — a prediction that increased up to $19 per share on Wednesday as demand went through the roof, according to an Associated Press report.

The company is known for, as the company’s name suggests, milkshakes, burgers, and crinkle-cut fries, and began as a lowly hot dog cart in Manhattan’s bustling Madison Square Park — just a handful of blocks north of the New York Stock Exchange, where investors gobbled its stock up this week. Its shares rose $24.90, a 119 percent increase, and closed at a whopping $45.90 on Friday, which would place the value of the chain at $1.6 billion.

Currently, Shake Shack has 63 locations that are mostly on the East Coast, with plans to expand farther, using the IPO as a way to fund the expansion plan. The company hopes to have 450 locations at some point, according to a regulatory filing.

Shake Shake is considered a fast casual restaurant chain that is still based in New York City. Its origins as a food cart go back to 2000. It faced some initial growing pains, but has developed a positive reputation in markets it has expanded to. The company revealed late last year in a filing with the Securities and Exchange Commission that it would be filing for an IPO.