The cakes, which symbolize the crowns worn by the Three Kings (or Wise Men) on their visit to baby Jesus, traditionally contain a little figurine for children as well as a dry fava bean.
Whoever finds the toy is crowned king or queen of the celebration, while the one who finds the bean has to buy the Roscón next year.
But this year, El Corte Inglés has promised an even greater prize. The Spanish department store says it has hidden one gram gold ingots in 250 of its cakes sold in the run up to Epiphany, worth €47.
It has also included one top prize of a gold ingot weighing an ounce with a value of €1,130.
El Corte Inglés sells as estimated half a million Roscones at its stores, in 25 different varieties.
The traditional sweet dough of a Roscon is scented with orange blossom and can be served with cream but is best when dunked into steaming mug of rich hot chocolate after an evening watching the Cabalgata – the lavish parades held across Spain on January 5th when the Three Kings distribute sweets and presents to children.