what changed? The short answer: World War I.

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Courtesy (C) Carnival Film & Television Limited 2011 for Masterpiece
“Downton Abbey’s” kitchen maid (Sophie McShera) and cook (Lesley Nicol) teach Lady Sybil (Jessica Brown-Findlay) the basics of cooking. Many Edwardian servants had a pretty good handle on advanced cuisines, says food historian Ivan Day.
As cookbooks of the era attest, middle and upper-class cooking standards were actually quite high before the war, Day says. “Some of it was very technically dazzling and difficult to do.”
Cooks and their assistants, he says, were often highly skilled at very advanced cuisines. Take, for example, the “fancy ices” that were all the rage at the end of the 19th century. Ambitious cooks would use specialized copper and pewter molds to create elaborate ice cream delicacies in the shapes of swans, doves, even asparagus — all without the benefit of modern refrigeration.