I'm wondering if that's a Danish idiom...
Google just translates it to "over the hot wheat" (or alternatively "over the hot wheat buns")
[Edit] Oops! My bad.... I see you were referring to the traditional buns you have for Store bededag.
It's not listed on this page:
https://guidetoiceland.is/history-culture/icelandic-traditions-holidays-dates
Nor on this page (less wordy, so easier to see the important stuff):
https://www.iceland.is/the-big-picture/people-society/traditions
I just searched for "Great Prayer day (Store Bededag) in Denmark" in Google.
I actually selected that text in your post, right clicked, and asked Google to search for it.
The first result was this page, in English:
https://en.wikipedia.org/wiki/Store_Bededag
Of course I just had to look that up...
Interesting tradition and history.
And a moveable feast, due to it being connected with Easter.
I see it's also celebrated in the Faroe Islands, where it is called Dýri biðidagur, and in Greenland (Greenlandic Tussiarfissuaq).
Enjoy the day, Tim!
Are you sure he's still a virgin?
Or is it just a case of getting rid of an existing brother, thinking that may make you eligible to join the WS brethren?