The most popular method of thermal processingin the Spanish gastronomy is boiling. Grilling foood is especially widespread in the north of the country, whereas roasting is the dominant technique in the central regions (mainly meat) and on the coast (mainly fish). Spain has also retained the custom of clay pot cooking in a special Spanish clay pot which is also used for serving the dishes that have been prepared in it.
In many regional cuisines the preferred culinary technique is frying (both meat and fish) in boiling hot olive oil. The basis of many sophisticated dishes is sofrito, which means searing chosen vegetables and aromatic ingredients in olive oil. Other traditional methods of cooking meat are the famous in the north of Spain pepitoria (thickening the gravy with hard-boiled eggs and ground almonds) and originating in Aragon chilindron (thick, heavy sauce made from tomatoes, pepper and onions which is cooked with meat).
In Spain there is a large group of enthusiasts of pickled vegetables, especially olives which are a very popular snack in the south, but the taste value of aubergines, garlic, onion or gherkins also has to be mentioned. There is also fish and poultry in vinegar brine. For meat preparation, Spaniards often use pepper marinade or different kinds of sauces such as mayo sauce, alioli (traditional garlic sauce), ajoarriero (a sauce made from potatoes, garlic, eggs and olive), ajo cabanil (a mixture of mashed garlic with vinegar, water and salt).
A popular snack all over the country is bocadillo (a kind of a baguette sandwich) occuring in different forms depending on the contents. The most common are bocadillos filled with tortilla, veal or calamares, although some bocadillos are made with simple ingredients such as cheese, chorizo or ham. More rarely eaten snacks are sandwiches (a toast bread sandwich) and medianoche (a sandwich with roast pork, ham, cheese and cucumber seasoned with mustard). More and more popular on the market is the sandwich mixto (a toast bread sandwich with ham and cheese) and its variety, with the addition of fried egg, called sandwich mixto con huevo.
Using spices in Spanish gastronomy is not a frequent practice. Usually, dishes are spiced with saffron or different kinds of pepper (choricero, nora), that is why the dominant colour in Spanish cuisine is red. It is the smoked pepper, with its characteristic, smoky aroma, that is added to traditional Spanish cold meat produce and stewed dishes. Black pepper,on the other hand, is a very popular spice for dishes such as a stew. Among the aromatic herbs that occur in Spanish cuisine there are laurel, thyme and rosemary whereas cloves and cinnamon are used in confectionery products.
