A very angry article in Arab America said that Israelis were taking credit for Palestinian culture.
Imagine what their headline would be if the Miss Universe contestants were only exposed to Jewish culture. They would be talking about Israel erasing Arab culture!
The fact is that some 20% of Israelis are Arab and their culture is part of Israeli culture no less than that of Mizrahi, Russian or Ethiopian Jews.
Now the official Palestinian news agency Wafa is quoting an Arab Israeli restaurant manager as saying that stuffed grape leaves made by the pageant contestants was Palestinian (and that there is no such thing as Israeli cuisine.)
No, stuffed grape leaves is not Palestinian.
There is disagreement over where it originated, but the best guesses are Greece, Persia or Egypt. I don't see any source that claims this is a Palestinian food.