Technically, duck sauce is an orange/apricot-based sweet sauce. But some people out there are all switched around about things. Plum sauce is the main source of confusion—it's thicker, blackish, tangier, and pastier than duck sauce. Plum sauce traditionally comes with duck dishes, even in China. It makes sense that some people call it duck sauce.
Somewhere along the line, Westerners must have related duck sauce to the orange sauce most often found on French dishes such as duck l'orange. And since duck sauce is an American invention that has nothing to do with traditional Chinese food, it's fitting then that it would derive its name from French culture.
The fact that there are two misconceptions about duck sauce—that plum sauce is mistaken for duck sauce and duck sauce mistaken for the sauce that goes on ducks—is merely a bizarre coincidence.
For those West Coasters who are hearing about this so-called "duck sauce" for the first time, if you are confused, rest assured, us duck-sauce enthusiasts have been too. But with these major findings from my research, we can start to put these questions to rest.
With a firm understanding of the essential nature of duck sauce, one can then delve into the fascinating world of ducksauceography.
In Massachusetts, New York, and through- out New England, the sauce in question is ubiquitous. As in, it is at every Chinese restaurant. Often, a fresh (hopefully) dish of it is waiting for you at the table when you take your seat. No Chinese meal is complete without it. And yet on the West Coast, you will never find it in a single Chinese restaurant. No one has any idea what you're talking about if you ask for it.
And while I haven't been able to get the grant funding yet to make a definitive map of duck sauce regionalism, I do know that as you travel south on the East Coast, it becomes less and less prevalent, until you hit Washington, DC. There, every Chinese place still has duck sauce, but only a handful actually serve it fresh. Instead, they'll toss a few condiment packets of the stuff your way—on request. The packets are labeled duck sauce, but I've always considered the contents a poor, chemical- tasting substitute for the real thing.
Down in Southern Florida, duck sauce flows like rivers, with almost every restaurant featuring it center stage on the table, no questions asked.
Supermarkets are the one exception to the rule. In California, you will sometimes find little jars of duck sauce in the Asian foods section. But most supermarket duck sauce sucks, so it hardly even counts at all.