One of the most popular summer snack (tapas) in Spain is the Boquerones en Vinagre. It is a fillet of anchovy in vinegar and olive oil. Traditionally, Boquerones en Vinagre are pickled with garlic and parsley greens. They are served with cold beer in small quantities, sometimes accompanied with olives, capers, or potato chips. It is not recommended to serve them with wine.
Madrid is located far from the sea, but seafood and fish are as popular here as meat. It can be found in any bar of the city. Yet, in Madrid, such anchovies are pickled only with vinegar, often significantly longer, so that the taste is more harmonious and tender. Once the fish has already turned white, vinegar must be decanted and olive oil added to fish.