In Chicago, people will put a lot of things on their hot dogs – often all at once. For instance, at the classic Chicagoan chain Portillo’s, a regular old “Hot Dog” comes with “mustard, relish, celery salt, freshly chopped onions, sliced red ripe tomatoes, kosher pickle and sport peppers,” a style indicative of the rest of the city. But one ingredient is notably absent: ketchup. To many Chicago natives, ketchup on a hot dog is considered a sin.

But ketchup giant Heinz apparently sees this aversion to one of America’s most popular condiments in another light: That’s over 2.5 million customers the company is missing out on (at least when it comes to hot dogs). So leading up to yesterday’s National Hot Dog Day, Heinz came up with a new strategy for luring Chicagoans into putting ketchup on their dogs… trickery!

In a silly advertising stunt, Heinz released a “new product” it named “Chicago Dog Sauce.” The brand then went out and convinced locals to give this strange new sauce a try on their beloved hot dogs. A video supporting the campaign shows that many people dug this new red dog sauce… that is, until the big reveal. Pull back the label: “Chicago Dog Sauce” is actually just classic Heinz Tomato Ketchup.