If traffic is light and you're feeling somewhat adventurous, I can recommend a pitstop at
Sizzle Falafel & Shawarma near St. John's University -- 186-15 Union Tpke Fresh Meadows, NY 11366... the chicken schnitzel, the falafel, and the lamb shawarma are all amazing.
After going there once before a meeting at St. John's, I've managed to sneak in two returns during LGA-JFK jaunts similar to yours (uber there, eat, then uber to JFK)... all thanks to AA's cancellation of the nonstop DCA-JFK flights...