There’s a Kashiwa udon shop called “Platt Pitt” on platforms 7 and 8 of Kokura station.
The udon has a sweet broth and is filled with gingered chicken and airy noodles that pair better than you could ever imagine. The shop is inside the train station, but that doesn’t stop people from buying a train ticket just to get a bowl of Kashiwa udon.

Don’t worry, you can refund your train ticket when you pay for the udon.