Within the gold foil wrapping of a Ferrero Rocher candy there is a is multi-layered confection that seems like some kind of magic straight out of Willy Wonka’s chocolate factory: a single roasted hazelnut, encased in a wafer shell filled with hazelnut chocolate, which is itself topped with chocolate studded with chopped hazelnuts.

When the Italian chocolatier Michele Ferrero introduced the treats in 1982, it is believed that he named them “Rocher” after the craggy rock grotto, called the Rocher de Massabielle, that marks the place where the Blessed Mother appeared to St. Bernadette in Lourdes, France.

The chocolates’ hazelnut-pocked surface bears more than a passing resemblance to the rock formation at Lourdes, a place that had a special meaning for Ferrero, who died on Valentine’s Day in 2015 at the age of 89.

A devout Catholic, Ferrero was known for his strong devotion to Our Lady. At the celebration of the 50th anniversary of the founding of his company, he said: “The success of Ferrero we owe to Our Lady of Lourdes; without her we can do little.”

As the third largest chocolate producer in the world, Ferrero had a lot to be thankful for. The Ferrero Rocher candies, along with Nutella, Kinder treats and Tic Tacs, brought in over $10 billion Euros in 2016.

Ferrero was said to have made an annual pilgrimage to Lourdes, taking his top manager. He also organized a visit to the shrine for his employees, and had a statue of the Virgin Mary placed in each of his company’s 14 production facilities around the world.