Another weekend, another deeply satisfying, simple dish. Tortilla española, also known as tortilla de patatas, is a true staple in Spain. (It has nothing to do with the Mexican tortilla, by the way, other than the superficial resemblance, being round and yellowish.) It's usually translated as a "potato omelet", though I would say that it's more like a crustless quiche with a potato filling than an omelet. Most Spanish families have a tortilla for dinner once or twice a month, if not more: sort of the functional equivalent of mac-n-cheese in the US (another excellent Simple Food, by the way). And you'll find a tortilla sitting on the counter of just about every bar in Spain, from which little pieces are served up to customers along with their small glass of beer or wine.
It's a simple, simple dish, a magical combination of just five ingredients: olive oil, potatoes, onions, eggs, and salt. The potatoes and onions, sprinkled with salt and cooked in the olive oil, create a composite that is soft yet al dente, savory yet sweet (from the slight carmelization of the onions), and wholly suffused with the deliciousness of olive oil. Add it to the substrate of the beaten eggs and you get pure, simple happiness in a 10-inch diameter circle.
Such an easy, uncomplicated dish, which is why it's so versatile. In my house it's often dinner on those random Tuesday nights when I haven't been shopping and don't have anything particular planned, because I can pretty much always count on having the few ingredents required to make a tortilla. At a party you can cut it into little squares, stick toothpicks in them, and you have an alternative to chips and salsa as sideboard munchies. In bars in Spain, as I mentioned, it's one of the most common little tidbits of food (you can call it a tapa if you want) served with a drink. Cold, you can slice it up, put it on a baguette with some mayonnaise, and you've got a great sandwich.
All in all, tortilla española reminds us of one of the best things about simple foods: you don't need a special occasion to have something wonderful to eat.