In Gotanda, down the street next to the Mitsubishi MUFJ bank across from the west exit (the one with the Seijo Ishii) of Gotanda station, is Toshoumen Seian Hanso. I will submit that this is the best toshoumen place on the lower left side of the loop. This place filled up quickly on a Saturday night, we were waiting at door for the opening at 5:30, and there were 2-3 tables reserved by the time we got in. They have various toshoumens, including the quite spicy red one, regular dan-dan toshoumen, yasai toshoumen, chashu toshoumen, etc. Also they have a special spicy red sauce sliced-chicken dish (垂涎鶏) and many other things on an interesting Szechuan-style menu, many dishes claim to be from Xi'an. The proprietor is very friendly and he and the staff will speak Japanese very slowly and understandably to you if you ask them - they long cylindrical tetsu nabe gyozas (ジュージュー鉄鍋ギョーザ) are very good and have a taste not always found in other gyozas. The toshomen can be shared by two people. It had very fresh chewy noodles and the broth is quite rich, it doesn't taste like some powdered togarashis were tossed into a pot of chicken broth. Also included are ground pork and string beans. Right next door is a regular Chinese place, I don't know if they are related or not - but this place seems good enough - many interesting things on the menu, including some crab soups, chinese hot pot, etc. Prices were pretty cheap - a side, the gyozas, shorompo, the soup and the chicken, plus two asahi chu bins for 4500 yen. Not too shabby.
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