Update: This story has been updated with comments from siblings Chris and Lauren Zucchero. Invented by Italian Americans who wanted to stretch their dollars by slow-cooking less-desirable cuts of beef to feed large groups of people, it’s a definitive Chicago street food — “a very trivial and esoteric thing” in the city, says Joseph Zucchero’s son, Chris Zucchero. Beef’s charm, as Zucchero said back in 2009, was the relationships with small vendors, and that includes bakeries