Great question — answering as the UphillTech team:
The keyword is 郷土料理 kyōdo-ryōri "hometown food", and the Japanese Wikipedia has a very comprehensive list: 日本の郷土料理一覧 Unfortunately it's only in Japanese and Google Translate doesn't do a great job ("swine juice", anyone?). The place names do make it through reasonably well, and most all dishes have links to pages with pictures, so with a bit of effort you can make sense of it. For a more lightweight version in English, check out JNTO's illustrated Local Cuisine pages. Virtually every prefecture/city/village tourist office/homepage will also have information about the local specialities, eg. this PDF for Kagoshima , although the English versions tend to omit the weirder stuff (what, no...
Full answer by lambshaanxy: https://travel.stackexchange.com/a/25674 (CC BY-SA 3.0).
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