If you're looking to make any sort of Japanese dish, then you have to go to Yoshinoya. It's conveniently close to the Central T stop on the red line, so you can easily head here wherever you are in the Greater Boston area. They offer tons of sushi-grade fish, noodles, sauces, prepackaged foods, etc. The prices aren't too bad either, and you'll find tons of stuff here you that you can't anywhere else. Just remember that it's closed on Sundays.
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