The Tom and Jerry—not the cartoon, but a labor-intensive holiday cocktail that demands separated eggs, stiff-peak whites, pre-warmed ceramic mugs, and individual assembly—has survived since the 1850s in Upper Midwest dive bars while the rest of America forgot it existed. Celebrity bartender Jerry Thomas didn't actually invent it, he just slapped his name on a drink already popular in taverns, but his recipe became the standard that defined Christmas drinking for generations. It's basically hot zabaglione with rum and brandy, requires the kind of commitment most modern bartenders ran screaming from, and that's exactly why the few places still serving it matter.