Shake Shack shares more than double in stock market debut

NEW YORK -- Investors are craving burgers and crinkle-cut fries.

Shares of Shake Shack Inc. more than doubled in the minutes after they debuted on the stock market debut Friday.

The New York-based burger chain raised $105 million, selling 5 million shares at $21 per share, more than had been expected.

Trading under the ticker symbol "SHAK" on the New York Stock Exchange, the shares closed at $45.90, up $24.90 on the day.

Shake Shack cooks its burgers to order and promotes its use of natural ingredients. The chain has 63 restaurants in nine countries. It plans to use some of the money raised to open new locations, including one in Austin, Texas.