Answer:
   
   Those are foods popular in some cultures in which Jews lived, but have
   zero religious significance. They are sometimes called "Jewish foods"
   because of their popularity among Jews, and because they bring back
   memories of one's ancestors who ate similar foods.
   
   In Ashkenazi communities, Gefilte fish goes beyond being a food of the
   larger community adopted by the Jewish community. In these
   communities, there was a custom to have fish, wine, and meat on the
   Sabbath. On the Sabbath, one may not separate "bad from good" such as
   removing bones from fish. (Good from bad, i.e. fish from bone is
   OK...) To simplify matters, it became popular to serve ground fish
   from which bones were removed.
   
   Another Jewish dish is cholent, a stew left to simmer throughout
   Shabbos, because this a) avoids cooking on Shabbos b) reaffirms the
   belief in oral Torah, permitting the use of a fire lit before shabbos,
   as opposed to the Karaites, who rejected the oral Torah and didn't use
   fire on Shabbos. The cholent is then eaten for the Sabbath afternoon
   meal.
   
   One of the problems with Jewish cooking is that you can eat an entire
   meal, yet not even 72 hours later, you're hungry for more. (:-)