Fortune cookies are not a Chinese tradition. They were popularised in California.
The cookie most likely descends from a Japanese cracker called tsujiura senbei, and was served by Japanese-American bakers in California in the early 1900s. Chinese restaurants adopted it later.
Why is this true?
During the Second World War, Japanese Americans were interned and Chinese-owned bakeries took over production. In China itself, fortune cookies are so unfamiliar that they are marketed as an American novelty.
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