Kungßhuner or kung huner show up in a number of sources. The recipe in the Königsberg MS is more basic than the version in Cod Pal Germ 551, but basically the same dish.
[] Wilthu machen Kungﬂhuner:
If you want to make Kungßhuner
Take fried chickens and chop them into small pieces. Take fresh eggs and mix them with ground ginger. Pour this into a white mortar that must be hot and add a little saffron and salt. Place it by the fire and let it fry.
There are several more recipes using the mortar as a cooking dish, something that seems to be a German specialty or affectation.
The Königsberg MS was preserved in the archive of the Teutonic Order in Königsberg (today Kaliningrad) in Baltic East Prussia, though its language suggests that it belongs to a Central or South German background. It is not associated with any name that I am aware of and is dated to the late 15th century purely on the scribal hand. The recipe types match South German sources of that time. It was published in Gollub (Hg.): Aus der Küche der deutschen Ordensritter. in: Prussia 31 (1935) pp. 118-124.