Nothing defines a country and its people so clearly as a national food—a  dish that, when done right, tastes like the country from where it came.

National foods are so easy to categorize because of what they represent. A few hundred calories can sum up a people’s history, values, and economy. That’s how we know pasta was popularized in Italy, where pre-Renaissance eaters realized the food was cheaply made and easily stored. Sushi’s origin story harkens back to Japan and an era with limited food access other than the nearby ocean. Apple pie became a symbol of American prosperity in the early 20th century thanks to an abundance of apples, planted, in part, by the American legend John Chapman (a.k.a. Johnny Appleseed).

Of course none of those are officially sanctioned national foods. But that’s the point—there is no official sanction, no one person gets to decide. An act of parliament doesn’t make a food widely adored any more than a president can decide whether his people are happy. Foods are collective decisions, chosen and perpetuated over time, tacitly agreed upon by generations all acknowledging that a particular item is our dish, it’s what we eat.

In Berlin, the dish of the past and present is the currywurst—a pork sausage boiled, then fried, then coated with ketchup and curry powder. How it tastes is less important than the fact that it’s everywhere, on corners, in shopping malls, easily found for lunch and for sale late at night. The longstanding proletariat snack is widely recognized as the national dish of Germany.

We wanted to find out how it happened, so we went to the Deutsches Currywurst Museum in Berlin. The museum, where foam sausages and giant dollops of ketchup hang from the ceiling, is a tribute to Herta Heuwer, the woman who invented the currywurst in 1948. As inflation and food shortages hit Germany after World War Two, Heuwer, who owned a fast food stand in Berlin, experimented with new ingredients to pair with sausage. Two of these were ketchup and the curry powder that British soldiers had brought from India. The dish caught on, as much for its good taste as for its common appeal. A cheap, filling and resourceful meal, it nodded toward German ingenuity and the eventual recovery of wounded post-war pride.

Currywurst is still the leading street food of Berlin. Nearly a billion are served every year. It probably wouldn’t win any culinary awards, but it’s not meant to. There’s lore around it, which is better than any evanescent food craze that chefs or food companies fiddle with. That’s not to say there isn’t room to innovate it. Restaurants and food trucks that serve currywurst have popped up around the world. Never mind that the currywurst was created as an alternative to more expensive meat. One New York restaurant sells a new-age form of the dish—yours with a turnip confit for $12.