In a large skillet over medium heat, cook the sausage and onion until the meat has browned. Throw the garlic in during the last minute.
Drain the sausage of excess fat, then transfer to a mixing bowl.
Add the sauerkraut, breadcrumbs, cream cheese, parsley, caraway seeds, and mustard. Mix well.
If it's not too soft, form into balls. If it is a bit soft, just refrigerate it for 30 minutes to an hour.
Set up the dredging station, starting with about 1/3 cup flour in one bowl, the beaten eggs in a middle bowl, then about 1/3 cup breadcrumbs in a final bowl. Preheat your oil to 360 F.
Working in batches, dip the balls in flour, then egg, then the breadcrumbs. Fry until golden brown, about 2 to 3 minutes.
Serve right away or keep warm in an oven heated to 200 F.