ARI SHAPIRO, HOST:
From Coca-Cola to Kentucky Fried Chicken, heavily guarded secret recipes are the key ingredient to some of the world's most famous culinary success stories. In Portugal, one family has been keeping the original recipe for the country's favorite dessert a secret for generations. It's a flaky egg custard tart. And while imitations can be found in just about any Portuguese bakery, Rebecca Rosman visited the shop where it all started and sent this report.
REBECCA ROSMAN, BYLINE: It's only midday, but already the Antiga Confeitaria de Belem has sold nearly 10,000 of its famous pasteis de Belem.
UNIDENTIFIED PERSON: (Speaking Portuguese).
ROSMAN: By the time the shop closes, they'll have sold 20,000 of the warm, flaky custard tarts all made in-house with great care.
MIGUEL CLARINHA: This is what we call in Portuguese the secret room.
ROSMAN: Owner Miguel Clarinha points to a large door in the back of the kitchen which I'm not allowed to enter. That's because behind it, three entrusted chefs are kneading huge slabs of the famous buttery and flaky dough. Aside from the owners, these three men are the only people in the world who know this recipe.
CLARINHA: Their names are Ramiro, Carlos and Vitor. The three of them have been working here for a long time - over 40 years. And they got to be chefs because they were good bakers, and also because they were someone that management trusted.
ROSMAN: While imitations known as pasteis de nata can be found all over Portugal - all over the world, really - these are called pasteis de Belem named for the neighborhood where they were invented and still baked today. Once the dough is made, it's cut into thin slices and hand-stretched onto individual round molds. After getting a pump of egg cream filling, the pastries are placed in a 750 degree Fahrenheit oven for 20 minutes.
CLARINHA: And after those 20 minutes, we're going to put them on a table for them to cool just enough to get them out of the molds and take them to our customers.
ROSMAN: This is my first one. It's - ooh (ph), it's still warm.
(SOUNDBITE OF CRUNCH)
ROSMAN: It's delicious. Ooh, I've got some of the pastry on my microphone (laughter).
Tourists and locals alike fill just about every inch of the spacious blue and white-tiled bakery located just outside Lisbon. Giles Williams first came to the shop on holiday from London 20 years ago. On his latest trip, he says he knew exactly where he was taking his friends once they landed at the airport.
GILES WILLIAMS: I said as soon as we got to Lisbon, this is what I want to do. So every time I come to Lisbon, I come here probably within about the first two hours 'cause they're just the best.
ROSMAN: And they have a holy history. The secret recipe for the pasteis was given to the shop from the neighboring Jeronimos Monastery, where the tarts were first invented in the 18th century. Miguel Clarinha says monks would use egg whites to start their clothing, and the leftover yolks became dessert.
CLARINHA: And it was only after 1820 when the monasteries were closed following a liberal revolution here in Portugal that the recipe was passed on to a businessman that used what used to be a sugar refinery to keep on making the cakes and started selling them at a small trading shop that existed where our front counter exists today.
ROSMAN: In the early 20th century, the shop was passed down to Miguel's family. They've been overseeing operations for four generations, a detail he thinks has made just as big a difference as the secret recipe.
CLARINHA: I think if this wasn't a family-owned business it would probably have expanded. The cakes would probably start being frozen and exported and franchised. And that's really not our philosophy. We'd rather focus on the quality and on the place itself. And, yeah, it's a lot of work, but it pays off whenever you see a customer smiling or saying good words about the place.
ROSMAN: Customers also say they don't need to know the secret kept behind that closed door. For NPR News, I'm Rebecca Rosman in Belem, Portugal.
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