Martinshörnchen

St. Martin's croissant is a croissant with white poppy-seed filling traditionally prepared in Poznań and some parts of Greater Poland region on the occasion of St. Martin's Day (11 November). On 30 October 2008, the name and recipe for rogal świętomarciński was entered in the register of protected designations of origin and protected geographical indications in the European Union. In Poznań, the tradition of baking St. Martin's croissants on 11 November certainly existed in 1860, when the oldest known advertisement for the pastry was published in Dziennik Poznański.

Source: Wikipedia