On New Year's Day, Portland restaurant Ava Gene's will be serving brunch to the hungry and hung-over masses. And amidst the frittatas, French toast, and grits, there will be Chef Josh McFadden's own favorite: pasta carbonara.

McFadden, who has cooked carbonara at New York Italian restaurants, fell in love with it for breakfast while living at the American Academy in Rome. A plate of spaghetti doesn't look anything like your local greasy spoon's 2-2-2 special, but McFadden says the dish is a whole lot more familiar than you might think. "It's literally the same thing as taking toast, putting an egg on the toast, and then putting said toast in your mouth. And with coffee? Amazing."

Yes, the refined starch takes the form of noodles. But the other basic breakfast building blocks — including a dose of something in the bacon family — are the same. Hot pasta (most often spaghetti) is drained and tossed with beaten eggs, cheese (Parmigiano or pecorino Romano), and cooked pork (guanciale, pancetta, and bacon all make appearances). The hot noodles cook the eggs, which set with the pork fat and residual cooking liquid to create a lusciously rich sauce, not too different from a hollandaise.

So how did a dish that hits these all-American notes come out of Italy? According to food historian Anthony Buccini, recipes for pasta dressed with fat, eggs and cheese (cacio e uova) go back well into the 19th century. But mentions of carbonara — the dish that adds cured pork to the mix — don't show up until after World War II. And, according to one popular theory, this might not be a coincidence.

"In effect," says Buccini, "the claim is that there was a joining together of American taste for — and supplies of — bacon and powdered eggs [thanks to military rations], with the local Roman love of pasta asciutta [a simple sauced dish]; Roman cooks came up with the recipe to make use of the American supplies and to satisfy the foreign troops, perhaps with some prodding from those troops who missed their familiar bacon and egg combination." It's a beautiful story of food traditions melding and evolving. But is it true?

Buccini is skeptical, noting there is "little in the way of compelling evidence" that carbonara was inspired by American GIs, rather than being a simple variation to a large family of traditional pasta dishes. The Oxford Companion to Italian Food also rejects the WWII theory, stating: "The absurdity of this at a time of hardship and intolerable shortages calls for no comment."

But others, like Jeremy Parzen, a food historian and translator who teaches at Italy's University of Gastronomic Sciences, think it's not so far-fetched to conceive of American tastes shaping Italian cuisine. "American culture played a huge role in how Italy developed after the war," Parzen explains. "Essentially after the war, with the Marshall Plan, we rebuilt Europe. And whereas the French became snobbish, the Italians embraced American culture. They embraced American film, American music... They love their own food, but they also love food from all over the world."

Until the definitive source of the carbonara is unearthed, the debate will continue. But there's one thing almost all Italian chefs agree on — do not include cream. While this is a creamy dish, its lusciousness should come from the emulsion you get when you toss the eggs with the hot pasta and pork fat. This does require a delicate touch to get right, but it's not much more than navigating tossing and temperature. Even with a hangover, it should be doable.

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