It is the oldest religious vow in Europe. Its origins date back to 1348, when the Black Death, which wreaked havoc across Europe, reached Puertollano, reducing its population to thirteen families. The terror of the people of Puertollano at the scenes caused by the plague led them to make a commitment by fulfilling a perpetual vow, renewed year after year to this day. This vow consisted of preparing a meal for the most needy, which would be held annually. A stew made with beef and potatoes is prepared the night before in thirty large metal pots. On a hearth set up next to the Hermitage of the Virgin of Grace, on the day of the festival, this meal is distributed among all those who come to this place. During these days, there are also folk songs, concerts, and a medieval market. It is celebrated 48 days after Easter Sunday.