The most common and most likely answer to this crossword clue is the 5 letter word KNISH
K
N
I
S
H
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The straight part
We know that "Jewish speciality," is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case jewish speciality, = knish.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does KNISH mean?
KNISH noun- An Eastern European Jewish, or Yiddish, snack food consisting of a dumpling covered with a shell of baked or fried dough