Shake Shack tycoon Danny Meyer is worth $400 million more than he was yesterday

The burger chain Shake Shack became a public company on Friday and investors ate up the stock.

Shake Shack's shares soared to $52 in early trading from their inital price of $21, adding more than $386 million to founder Danny Meyer's net worth.

Meyer owns 7,440,822 shares of Class B stock of Shake Shack, according to regulatory filings.

Meyer is already a very wealthy man.

He's the founder of Union Square Hospitality Group, which has owned more than a dozen renowned restaurants, including Union Square Café, Gramercy Tavern, and Blue Smoke.

Meyer, 56, is also the recipient of accolades such as the James Beard Foundation's Restaurateur of the Year award and Humanitarian of the Year award.

He founded Shake Shack in 2004. The chain has exploded in recent years, going from seven locations and $19.5 million in sales four years ago to 63 locations and $82.5 million in sales today.

Shake shack sells burgers, milk shakes, frozen custard and drought sodas.