I cook the German version of the dish. It is called "Kutteln" - which would translate to "guts"! It is based on a roux and usually has vinegar giving it a nice hefty taste. Unfortunately no connoisseurs that appreciate this dish in my family, so largely it is for myself. I usually get the tripe for it at Ranch 99 or the local mexican market.
https://en.wikipedia.org/wiki/Saure_Kutteln
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