Kentucky Fried Chicken created a new paradigm for sandwiches when it replaced the bread bun with fried chicken in its Double Down. McDonald’s has a chance to reclaim the primacy of the sandwich with the Filet-O-Knish: dough wrapped German dumplings sitting nicely inside a fluffy, white bun. Tartar sauce? Of course. Guten appetit!

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Who said a sandwich had to have protein in the middle? The Filet-O-Knish sandwich would bring together bread, fried dough, and potato dumplings, for a starchy German treat.