Not Mayo Or Tartar Sauce: Would You Try A Filet-O-Fish Belgian-Style?

The introduction of the Filet-O-Fish sandwich back in 1962 changed the trajectory of McDonald's restaurants. At the time, branching out from the beef-focused menu of the moment was about bringing in Catholic diners on Fridays, but the first major McDonald's menu addition did more than meet that market desire; it was also a first step toward the customization and regionalization of the chain's menus around the world. Nowadays, the menu at McDonald's restaurants varies tremendously by location, with even seemingly familiar items like the chain's signature fish sandwich arriving with slight tweaks, as is the case with the McFish in Belgium.

McDonald's most famous seafood offering is the Filet-O-Fish sandwich, a crispy square of fried Alaskan pollock topped with tartar sauce and half a slice of American cheese on a steamed bun. In some other global markets, like the U.K., this recipe is little changed, though they may spell it "tartare sauce" on that side of the pond. Pop across the English Channel to Belgium, however, and things are a bit different. It's widely known that Belgians dip their fries in mayonnaise, and these unique sauce selections extend to fish sandwiches as well. 

With Belgium's McFish sandwich, the steamed bun and fried fish remain, but it is served without the cheese, and the creamy tartar sauce is swapped out for ketchup. Mayonnaise on French fries and ketchup on fried fish: It may sound backward to customers in the U.S. market, but it is actually fairly widespread — and popular.

The style of sauce found on the McFish sandwich is not unique to Belgium, extending as well to other parts of the European market. In Cyprus, Spain, and the Netherlands, for example, this same offering is available. Notably, however, McDonald's restaurants in each of these countries also carry the original Filet-O-Fish sandwich. Just as with the introduction of that first Filet-O-Fish, the seemingly unusual flavor combination in the McFish is there to give diners more variety in their sandwich options. 

Looking at McDonald's menus from around the world, this ketchup-smeared fried fish patty is far from the only variation on the chain's signature fish sandwich that you will find. Ordering a Filet-O-Fish French style — the McFish Mayo — means no cheese and just a simple swipe of mayonnaise on the bun for sauce. The Norwegian addition to the Filet-O-Fish on menus, on the other hand, is the Fish McFeast, a fish sandwich dressed up much more like a traditional burger with all the fixings. 

Head down under, and the sandwich looks nearly the same, but the Australian Filet-O-Fish sandwich differs in terms of the protein used, with hoki making an appearance. In some Asian McDonald's restaurants, you can also find a Filet-O-Fish topped with a nose-tingling wasabi-infused sauce. Even within the U.S., there is some degree of variation, with certain McDonald's offering a tartar sauce made with Old Bay seasoning. The Filet-O-Fish arrived to fill a niche, and with minor tweaks, it continues to do so in markets around the world.