Soomen (そうめん) and Zarusoba (ざるそば)
Popular Summer Dish – Noodle
(Typical Soomen Noodle Served Cold in Summer)
Soomen (素麺／そうめん) is a name of the kind of very thin noodle, but the dish itself is called Soomen. No Japanese has Soomen in winter. This is definately a summer item, which is cooked at home or served at traditional Japanese restaurants. Usually, it is made of flour and its color is white like the one in the picture above.
At table, Soomen is served with special dipping sauce called Soomen Tsuyu (つゆ). Since Soomen noodle is so simple, people tend to add some additional flavor mixed with the needle itself or to serve Soomen along with seasonings called Yakumi (薬味／やくみ) or additional dishes.
(Examples of Yakumi)
(Restaurants serve Soomen like this!)
Along with Soomen, there is another kind of noodle called Soba (蕎麦／そば) made of buckwheat, which makes Soba dark grey or brown. Noodle of this kind is served cold like Soomen with Soba Tsuyu.
Zarusoba got its name from the utensil called Zaru (https://en.wikipedia.org/wiki/Zaru), on which Zarusoba is served. Unlike Soomen, it must come with Wasabi (わさび：https://en.wikipedia.org/wiki/Wasabi) horseraddish. The Japanese tend to use it in the form of powder because it is very affordable while some like a tubed one like toothpastes, which costs more than powder Wasabi. On the other hand, restaurants tend to serve the authentic horseradish, which customers grate it by themselves, shown in the picture above.