Tortilla de Patatas: The Spanish Potato Omelet, With Onion or Without
Spain's Centro de Investigaciones Sociológicas is a state institute that normally measures voting intentions and trust in the government. In 2024 it put one more question to 4,024 people: does onion belong in a tortilla? 71.8 percent said yes, 21.3 percent said no, and nobody found it odd that the state was asking.
Tortilla de patatas is an omelet of potatoes cooked slowly in olive oil, bound with beaten eggs and cooked on both sides in the pan until it sets into a round cake - and in Spanish cooking it's a dish everyone has an opinion about. I do too. No onion.
A Little Cake That Means Something Else in Mexico
The name is a diminutive: torta is a cake or a flatbread, so tortilla is a little cake, named for the round shape it comes out of the pan in. The Spanish took the same word to the Americas, where it stuck to the corn flatbread, so the egg version has to go by tortilla española over there for anyone to know what you mean. At home it's the national dish, no question: they make it from Galicia down to Andalusia, the Basque Country and Alicante hold their own regional championships, and the Portuguese, to their credit, call it tortilha espanhola. The cousins sit around the Mediterranean. The Italian frittata uses the same ingredients but never gets flipped - it finishes in the oven. The French omelet is folded, and potatoes have no place in it.
Onion Was in the Tortilla Before Potatoes Were
The oldest written recipe for a tortilla dates from 1599, and you will find onion in it. Potatoes you won't. The Spanish brought those back from the Andes in the sixteenth century and spent two hundred years distrusting them: they grow underground, they're related to deadly nightshade, and the Bible doesn't say a word about them, so they ended up as cattle feed. Nobody knows when someone first dropped them into eggs. Who gets to say "it started here" is disputed, with a legend on one side and a letter on the other. The legend credits the invention to the Carlist general Zumalacárregui in Navarre, and it circulates in two versions that contradict each other, as legends tend to. The letter is dated February 27, 1798, signed by José de Tena Godoy, and it proposes a cheap dish of potatoes and eggs to fight hunger. The Extremaduran town of Villanueva de la Serena took him at his word: it throws the tortilla an annual festival, and in 2021 it put up a five-meter monument to it, a wedge speared on a fork - historians still won't commit to a birthplace as firmly as the sculptor did. Sincebollistas like me take one lesson from all this: the onion was there before the potato.
Three Ingredients and One Flip
A tortilla needs nothing but potatoes, eggs and olive oil, and people still find plenty to argue about without ever mentioning onion. The potatoes are sliced and go into the oil to poach rather than fry, until they soften - then they're drained, folded through beaten eggs and returned to the pan. The decisive moment comes halfway through: you cover the tortilla with a plate, turn the pan over in one motion and slide the omelet back in raw side down - it's called dar la vuelta, and it's a test no spatula will pass for you. The second article of faith is the center: in Betanzos, in Galicia, they make it so runny that it pours out of the wedge onto the plate, and the last two national championships went to cooks working in the Betanzos style.
People eat it at any time of day: in the morning with coffee, at midday as the first course of the menú del día, at the bar as a tapa or as a pincho de tortilla, a wedge on a piece of bread that belongs to a Madrid morning as much as coffee does. It's just as good cold, which is why it ends up in a baguette on the beach or on the train. If you want it runny, you ask for it poco hecha at the bar; if you want it set through, muy hecha. According to the same CIS survey, the first group is in the majority. Bar Néstor in San Sebastián makes two tortillas a day, at one and at eight, cuts each one into twelve slices and won't give anyone more than one; the line forms an hour ahead. Turning up late is the only way to miss out.
Tortilla for Breakfast, Hold the Onion
In Spain I like it best in the morning, as part of a typical Spanish breakfast: a wedge, a bit of bread, coffee. The one I keep going back to has nothing in it but potatoes and eggs. It should still be soft inside; the way I like scrambled eggs, I want it a little runny. The potatoes fall apart under the fork, the egg barely holds them together and the oil binds it all without tasting greasy. I don't miss the onion. By the CIS numbers I'm in a twenty-one percent minority in Spain. The last two national tortilla champions are in there with me.
