This is an excerpt from Een notabel boecxken van cokeryen
(Netherlands, ca. 1510 - C. van Tets, trans.)
The original source can be found at
Willy Van Cammeren's website
Another green sauce. Take parsley and beet leaves or [other] green leaves and grind that up in a mustard mill with vinegar and put into it spices, ginger and grains of paradise.