Considering that Spain has 19 olive oil-producing regions and provides more olive oil than any other country in Europe, it's not surprising to find this to be an essential ingredient in tapas. The golden liquid extracted from the fruit of the olive tree has been the basis of Mediterranean cooking since biblical times. Olive oil is just as popular in today's kitchen as it was in the age of the Greek and Roman empires and is certainly more widely used. Apart from the range of delicate and suggestive flavors it can add to almost any dish, olive oil is an excellent source of monounsaturated fat, which helps lower LDL (bad) cholesterol while maintaining HDL (good) cholesterol. It is also an important source of vitamin E, which researchers believe reduces the risk of coronary heart disease, some types of cancer, and arthritis.

—L.E.