Soba Mugi Ichi

Small soba shop, cozy and dark, even at midday; walls, floors, and tables are all dark woods. Its storefront is recognizable by a panel of deep blue roof tiles over the doorway. There are only a few tables inside, but noodle shops are not places to linger. Its in a busy enough area to cater to tourists; they have a good English-​language menu that was vetted by someone with decent knowledge of English (i.e., without the unintentionally hilarious errors often seen in such menus).
Over a dozen soba options (at least on the English menu), most offered both hot and cold, with a variety of toppings. Prices range 600 to 1100 yen, depending on topping, which include scallions, grated yam, rice cakes, mushrooms, natto, seaweed, oyster, rice cakes, shrimp tempura, duck meat and leek, and deep fried tofu. Cold soba can be ordered just with bonito broth or curry soup for dipping. For an additional 200 yen, a large «helping» of noodles can be had.
The cold soba with nameko mushrooms was deliciously earthy, nutty, and refreshing; the gelatinous coating on the mushrooms complemented well with the soba, nicely accented with sprouts, carrots, wasabi, seaweed, and sesame seeds. It comes in no broth, essentially just the «sauce» from the mushrooms and soba cooking liquid. Hot soba with duck meat and leek was heartier and flavorful; the hot soba with deep-​fried tofu good. Soba noodles are not as good as housemade ones I’ve had elsewhere in Japan, but are good versions in texture.
Good stop for soba noodles near Shinjuku station.