Boudin Bakery (Anglicized pronunciation: boo-DEEN) is a bakery based in San Francisco, California, known for its sourdough bread (trademarked as "The Original San Francisco Sourdough"). The bakery is recognized as the "oldest continually operating business in San Francisco." It was established in 1849 by Isidore Boudin, son of a family of master bakers from Burgundy, France, by blending the sourdough prevalent among miners in the Gold Rush with French techniques. The first outlet outside California was established in 1979 in the Yorktown Center mall in Lombard, Illinois. It closed in mid-2009.