Eating what you catch is very important because Spaniards hate wasting food and will try to utilize every part if the animals they eat. Also, although tomatoes are not originally from Spain, you'll find them in many dishes. Since tthey were brought to Spain in the 16th century, Spain has become one of the largest producers of tomatoes in the world.
La tortilla is more closely associated with the interior part of Spain, like Salamanca. This region is called La Meseta and includes the autonomous communities of Castilla y León, Castilla de La Mancha, Extremadura, and Madrid. Here, the winters are a lot colder than on the coast so they grow foods like onions and potatoes. For that same reason, the food here tends to be more hearty. There are many foods like the tortilla that are dense and substantial.
