Despite the obvious inference, it is today believed French fries originated not in France but in Belgium. A Flemish manuscript dating to 1781 contains the first reference to the fried potato. Today, frites pair with another quintessential ingredient of Belgium, mussels, to create the national dish: moules-frites, a comfort-food dish popular throughout other parts of Europe, particularly in France.

Mussels, once considered a food of the poor, were eaten in the winter months in Belgium, when no other seafood was available or abundant. As were potatoes. The dish peaked in popularity after World War I, when friteries popped up across the country, churning out the dish in large quantities affordably.

Moules-frites remains ubiquitous in modern-day Belgium, a social dish that brings people around a table to enjoy bowls of steaming mussels and perfectly fried frites. The dish is served in separate bowls so the French fries do not become saturated and soggy, the mussels typically displayed in the same pan and stock they are cooked in. The best mussels come from the Scheldt, a shallow river connecting Western Belgium to the Netherlands. Mussels should be shaken during preparation to ensure they cook evenly. The bintjes potato is preferred for frites due to its high starch content; the potatoes are typically double-fried with a hint of cayenne. While a variety of sauces may be available, mayonnaise traditionally accompanies the dish.

Moules-frites can be found anywhere in Belgium, but it doesn’t have to be the same each time you enjoy the dish. Several popular variations for the mussels exist. Perhaps the most popular, mariniéres prepares the mussels in white wine, shallots, parsley and butter. A simple preparation, au vin blanc mussels are cooked in white wine. Natures means the mussels are prepared with celery, leeks and butter. À la crème is similar to the mariniéres version, but with flour and cream for a thicker consistency. À l’ail, another popular method, marries the mussels with sliced or minced garlic.

More modern interpretations of moules-frites infuse the steaming liquids with different flavors, such as smoky chili or curry, or with another traditional Belgium staple, beer — moules à la bière. Also increasing in popularity is moules parquées, mussels served raw on a half-shell with a lemon-mustard sauce.