Simmering dried white beans with chopped tomatoes (or tomato puree) and other vegetables such as carrots, onion, parsley, celery, and bay leaves, with lashings of olive oil.
(Recipes vary considerably and lima beans are sometimes used instead of white beans.)
The dish originates in ancient Greece, as a sort of vegetarian stew of beans, vegetables and grains, and was used as a sacrifice to the Greek God Apollo at the Pyanopsia festival.
According to the myth, the custom was born when Theseus sailed from Athens to Crete to kill the Minotaur. On the way, he stopped in Delos island (right by Mykonos), and made a sacrifice to Apollo, promising that if he manages to win the battle and kill the beast, he would offer the God olive branches decorated with fresh fruit, to thank him.
On his return, following the adventure in the Minoan palace labyrinth, Theseus stopped in Delos again, to fulfill his promise. However, it had been seven days since their departure and no food was left on the ship. So, Theseus’ shipmates gathered anything they could find, and cooked it in a stew, making the original fasolada.