Austria's famous chocolate cake the "Original Sacher-Torte" celebrated its 175th birthday.
The bash was organized by Vienna's prestigious Hotel Sacher that produces the cake distinguished by its chocolate seal and sold in a wooden box complete with golden corners from a secret recipe locked away in a safe.
"There is only one original," Elisabeth Guertler, who runs the hotel, told reporters before the start of the festivities.
Over the years, the hotel has fought others including its famous competitor Demel arguing that only it has the right to call its cake the "original."
The hotel, situated opposite the Opera in central Vienna, claims the cake came about by mere chance in 1832 when Franz Sacher, an apprentice at the court of Prince Metternich, had to come up with a dessert when he was filling in for his sick boss.
Guertler stressed that only natural products are included in the secret recipe, including eggs, flour, butter, jam and sugar. Not to be forgotten is the chocolate coating.
Over the years, the handmade cake, which is traditionally eaten with a glob of unsweetened whipped cream, gained global recognition.
Currently, about a third of the roughly 360,000 cakes produced each year are exported to countries around the world. Germany tops the list of Sacher enthusiasts, followed by the United States, Italy and Switzerland, according to statistics provided by the hotel. Cakes which can keep for several weeks _ come in various shapes and sizes and also in the form of dice.
The hotel says actress Sharon Stone and actress-model Liz Hurley are among the cake's "celebrity fans" and that even the Pope enjoys a slice from time to time.
Caballe, for one, seemed eager to get a taste after she briefly serenaded an oversized version of the cake on the hotel rooftop in bright, spring sunshine.
"We're celebrating our birthday together," said the singer, who was born in Barcelona, Spain, on April 12, 1933, as she delicately savored her bites.
Caballe noted that the cake brought her luck years ago when she first came to Vienna for a performance.
She didn't seem too concerned about potential negative side effects of the tasty treat.
"Calories don't exist!" Caballe noted with a laugh.