Last week, Italian gourmets celebrating one of the country's classic pasta dishes -- carbonara -- had a simple message for foreigners: keep it simple, and don't betray the tradition.
"The secret to a good carbonara... is more about what you don't put in it, rather than what you put in it," food journalist and carbonara expert Eleonora Cozzella said.
She was speaking on the sidelines of the launch in Rome of the "Carbonara Day," a once-a-year online marathon of carbonara-themed events organised by Italy's pasta-makers' association.
Classic carbonara, typical of Rome and its surrounding Lazio region, is made with eggs, pork cheek (guanciale), pecorino cheese and pepper. Italians get touchy when more ingredients are added to the mix.
Earlier this year, a "Smoky Tomato Carbonara" recipe in the New York Times' cooking supplement, which included tomatoes and replaced pork cheek and pecorino with bacon and parmesan, caused an uproar in Italy.
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Coldiretti, a farmers' lobby, called the US recipe "a disturbing knockoff of the prestigious dish from Italian popular tradition," and complained that carbonara was "one of the most disfigured Italian recipes".
The dish actually owes its origin to the United States, as it was developed in Rome towards the end of World War II, when invading US soldiers brought bacon to poor and starving Italy.
A spokesman for the pasta-makers association, Matteo de Angelis, said even some old Italian recipes for carbonara -- from the 1950s -- included incongruous ingredients such as garlic and gruyere cheese.
Cozzella said she is "never scandalised" by unorthodox variations on carbonara. But she added: "Some versions may be seen as a homage, and other ones more as an insult."
"The important thing is never to cross the line that betrays the spirit of the dish. The problem is never tradition versus innovation, but tradition versus betrayal," she concluded.
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The article has been lightly edited for style.