Cook your buckwheat noodles according to package instructions; usually boil them for only a few minutes. Drain and rinse. Set aside.

Cut the cucumbers and grate or puree the radish

To assemble and serve: (you can either serve the Zaru Soba with the sauce already poured in or in a separate bowl; serving separately is the more traditional way of eating this dish) Serve the noodles and top with the fresh cucumbers, radish and nori. Alternatively, you can simply add the pureed radish into the dipping sauce and mix slightly. Serve with wasabi and enjoy.