Why go
Look for Rheinischer Sauerbraten, Himmel und Äd, Reibekuchen or Düsseldorfer Senfrostbraten according to appetite. Their different flavours give a more useful picture of local cooking than one supposedly definitive restaurant list, and make a traditional brewery meal easier to choose.
The full story
Rheinischer Sauerbraten is a marinated pot roast associated with the wider Rhineland. Himmel und Äd, or heaven and earth, brings black pudding, potato and apple together; the name plays on apples from trees and potatoes from the ground. Reibekuchen are fried potato pancakes, often served with apple sauce. Düsseldorfer Senfrostbraten puts local mustard on a roast or steak, making the city's strong mustard part of the main dish rather than a side condiment. These foods serve different moments: a roast is a substantial meal, while potato pancakes can make a smaller stop during a day out. Menus and kitchens change, so treat the dish names as things to look for rather than a promise that any particular place serves them. If you are already in the Altstadt for Altbier, a regional meal can extend that cultural thread without turning the day into a tour of addresses.