I'm a native Jewish NYer who has also lived in Los Angeles, and I can assure you that there has never been potato bread to be found in delis or in anybody's traditional family table. You cannot bring your own bread. You should choose club or rye...you may never have eaten decent rye bread.
Yes you are more than welcome to bring in your potato bread. ..
Best thing you can do is to contact the management of Sarge's and ask.
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