Cologne - or nearby - has some of the best restaurants in Germany:
19 from 20 points GaultMillau:

STEINHEUERS REST. ZUR ALTEN POST, BAD NEUENAHR
RESTAURANT DIETER MÜLLER, BERGISCH GLADBACH
VENDŌME, BERGISCH GLADBACH
ZUR TRAUBE, GREVENBROICH

http://www.gaultmillau.de/gmd/best.php3

Or Michelin:

5 with one Michelin star

http://www.viamichelin.com/viamichel...er/Restaurants

Or here:
http://www.der-feinschmecker-club.de...endlyURL=guide