What are Yasaburo and Professor eating in episode 9? What are these huge donut-like things the characters are eating in the office? From the distance it looks like cylindrical donuts, but a closer look shows it's some sort of puff roll cake. I understand that the size is greatly exaggerated, but what kind of pastry is this?




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This is from the episode 9. I remember this site had an event recently where the users were proposed to watch and then discuss this episode or something like that. I wonder if this was discussed there.
To me, it looks like Baumkuchen, a german cake.