Caldillo de perro (lit. dog soup) is a traditional Andalusian soup originating from El Puerto de Santa María. The soup is usually made with a combination of fresh hake, olive oil, onions, Seville oranges, garlic, and stale bread. The garlic is fried in oil, then discarded.
The onions are fried in the same oil, then mixed with water and cooked until soft. The pieces of hake are added to the pot and boiled, and near the end of cooking the juice of Seville oranges is mixed in, along with bits of bread. This soup is traditionally served warm in an earthenware plate called cazuela de barro.