Depending on where you go in Tokyo, there aren't always a lot of ramen places open at 11 AM on a Saturday morning. Shinjuku Sakura Fubuki, a chain of 5 stores in Tokyo (the other store is in ShimoKitazawa), Chiba and Fukuoka, was open and I went to it since my first pick of the day was closed on Saturday in spite of what various ramen magazines indicated. It's right next to the Shinjuku 3-chome (check) Keika, you can see the edge of the Keika sign in the above picture. Shinjuku Sakura Fubuki had a serious line inside of about 15 people sitting on a long bench, lots of people who looked like they worked in the local entertainment industry. This store's main dish is tonkotsu ramen, although they do have a tonkotsu-miso blend soup available. I had the tontoro (豚とろ) which was a special version of regular tonkotsu with paperthin slices of extremely fatty pork, each was perhaps matchbook sized and 75% clear fat. The good broth had a deep tonkotsu flavor, but not exactly like tonkotsu, more like tonkotsu with shio added or similar. The service was very fast moving for such a cramped store. There are containers of tea on the table. However the noodles were on the plain side and while it was good overall, I'm not sure it was worth 1150 yen.
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