Looking for an asian market
I am not sure what shishito peppers are, but pre-packaged fried tofu is ubiquitous in the Asian stores around town.
Go down to Argyle Street. There are at least 2 large(r) grocery stores to check out. There are also 2 large(r) ones on Broadway St. 1 is 1/2 a block south of Argyle and the other is about 1 block south.
You can always try Chinatown stores too.