Sourdough was a type of bread. At one point, when the human boy Anakin Skywalker was told by his mother, Shmi Skywalker, that his lunch would be a PB&J on rye bread, he initially got angry due to the lack of white bread, but he exclaimed joyfully after he was told that sourdough bread was available instead.
Sourdough was mentioned in "Exit from Endor," the second episode of the non-canon animated series LEGO Star Wars: Droid Tales, which aired on July 6, 2015.
Sourdough was mentioned in "Exit from Endor," the second episode of the non-canon animated series LEGO Star Wars: Droid Tales, which aired on July 6, 2015.