I am posting this for my father, who tried a version of this recipe at the Sion Brauhaus in Cologne, Germany when he was here visiting us. He enjoyed it so much, that he asked me to find a recipe for him. This recipe, as translated directly from the German version I found in "Koch Vernuegen Wie Noch Nie" is very close to what he tried. Bacon grease is really quite essential here for the flavor - please try not to use a substitute as it just won't taste quite the same. You may use any type of cooked sausage you like, however, if you decide to throw some in at the end of the cooking process. In the area of Germany I currently live in, you would most often see bratwurst added to the kale. I am guessing on the cook time as I have not acutally made this myself yet. I will warn you that this is a very ugly looking dish and may be considered an acquired taste for some, although I find it quite delicious personally.