A very good veggie Udon soup is on the lunch menu at (rather new) Japanese restaurant Hashi Izakaya, Rosenthaler Str. 63, 10119 Berlin.
What I love about Berlin are its absurd phenomena which can be discovered off the beaten tracks, existing mostly only out of the generosity (or ignorance) of the municipal administration in (more or less) public spaces throughout the whole city. One of those is the Thai Market in Wilmersdorf.
Another great Udon soup with a dainty aromatic broth at a favorite Udon place: Smart Deli.
A recommendation for a day in May, that’s way too cold: Korean Kimchi soup at Yam Yam, Alte Schönhauser Straße 6, 10119 Berlin Mitte. A huge bowl filled with delicious broth and spicy Kimchi, accompanied by spinach in sesame sauce and rice will keep you warm until the sun comes back.
The Smart Deli opened its doors in February 2002 in Friedrichshain and moved to Mitte last year to a much bigger store.