So although it’s true that Chinese restaurants were notably open on Sundays and during holidays when other restaurants would be closed, the two groups were linked not only by proximity, but by otherness. Jewish affinity for Chinese food “reveals a lot about immigration history and what it’s like to be outsiders,” she explained.

Estimates of the surging Jewish population of New York City run from 400,000 in 1899 to about 1 million by 1910 (or roughly a quarter of the city’s population). And, as some Jews began to assimilate into American life, they not only found acceptance at Chinese restaurants, but also easy passage into the world beyond Kosher food.

“Chinese restaurants were the easiest place to trick yourself into thinking you were eating Kosher food,” Ed Schoenfeld, the owner of RedFarm, one of the most laureled Chinese restaurants in New York, said. Indeed, it was something of a perfect match. Jewish law famously prohibits the mixing of milk and meat just as Chinese food traditionally excludes dairy from its dishes. Lee added:

If you look at the two other main ethnic cuisines in America, which are Italian and Mexican, both of those combine milk and meat to a significant extent. Chinese food allowed Jews to eat foreign cuisines in a safe way.

And so, for Jews, the chop-suey palaces and dumpling parlors of the Lower East Side and Chinatown gave the illusion of religious accordance, even if there was still treif galore in the form of pork and shellfish. Nevertheless, it’s more than a curiosity that a narrow culinary phenomenon that started more than a century ago managed to grow into a national ritual that is both specifically American and characteristically Jewish.

“Clearly this whole thing with Chinese food and Jewish people has evolved,” Schoenfeld said. “There’s no question. Christmas was always a good day for Chinese restaurants, but in recent years, it’s become the ultimate day of business.”

But there’s more to it than that. Ask a food purist about American Chinese food and you’ll get a pu-pu platter of hostile rhetoric about its inauthenticity. Driving the point home, earlier this week, CBS reported on two Americans who opened a restaurant in Shanghai that features American-style Chinese dishes such as orange chicken, pork egg rolls, and, yes, the beloved General Tso’s, all of which don’t exist in traditional Chinese cuisine. The restaurant gets it name from another singular upshot of Chinese-American fusion: Fortune Cookie.

Schoenfeld, whose restaurant features an egg roll made with pastrami from Katz’s Deli, shrugs off the idea that Americanized Chinese food is somehow an affront to cultural virtue. “Adaptation has been a signature part of the Chinese food experience,” he said. “If you went to Italy, you’d see a Chinese restaurant trying to make an Italian customer happy.”