The recipe occurs twice in Cgm 484 II, with only slight variation:
23 Galantine (galray) for a goose
A garlic galantine for a goose: Take a young goose that is prepared well and nicely and roasted. Take with this garlic and white bread in equal quantities and pound that. Take vinegar and honey with it and pass it through before (czuich es vor durch). Spice it if you wish. But it is not common (nit gewonlich).
29 Galantine for Roast Goose (brauten gänß galray)
Take a young goose when it is well prepared and roast it very nicely. Take garlic and the same quantity of white bread and pound that in a mortar, and pour in wine and vinegar and pass it through a cloth. Then pour in honey and boil it up, and spice it well, then you have a good galantine (galray) with the goose.
This is almost the same recipe, really. Garlic is a very common condiment with goose throughout the German corpus, so this is not surprising. As a spicy sauce thickened with bread, the preparation described here also fits the description as a galray by the lights of the collection. Presumably that means it would be served cold. The most salient difference between the two is the final sentence in #23 that it is nit gewonlich. Depending on the context, this phrase can be read as meaning simply that something is not commonly done, but also that it is the opposite of common, something refined. I assume that it is supposed to mean adding spices is not commonly done, but that is speculation on my part. It could equally be intended to point out that (despite containing garlic) this is not a commonplace sauce.
Again, there is a close parallel in the Rheinfränkisches Kochbuch:
36 If you would make a sauce for a goose, take a young goose that is well fed and roast it nicely. Then take garlic and white bread in equal amounts and pound it well, and pour wine and vinegar with it. Pass it through (and add it to the goose), and season it well because saffron takes away the (strong) savour.
Note that this text does not call it a galray. Here, we learn that saffron is used to mitigate the intensity of garlic. I suppose this would require a significant and expensive amount. The resulting sauce would be yellow rather than white.
Bound together with medicinal, veterinary, and magical texts, the culinary recipes of Munich Cgm 384 were partly published in 1865 as “Ein alemannisches Büchlein von guter Speise“. The manuscript dates to the second half of the fifteenth century. My translation follows the edition by Trude Ehlert in Münchner Kochbuchhandschriften aus dem 15. Jahrhundert, Tupperware Deutschland, Frankfurt 1999, which includes the first section of recipes not published earlier.