SALT LAKE CITY — The condiment pumps at Crown Burger rarely get a break. But it's not ketchup that's getting all the action, and customers barely give mustard a glance.

Instead, it's a pink-colored delicacy known as fry sauce that customer after customer squirts into paper cups. And it's a scene that repeats itself at thousands of restaurants and homes across Utah every day.

While most Americans top their fries with ketchup, and tradition calls for mayonnaise or vinegar in Europe, for more than 50 years, a blend of mayonnaise and ketchup has ruled in Utah.

The result is that fry sauce is as much a part of Utah's popular culture as skiing and the Mormon church. There are fry- sauce souvenir T-shirts, a local band called Fry Sauce, even an Olympic fry sauce pin that was wildly popular during the 2002 Winter Games in Salt Lake City. (Collectors note: the pin has been spotted on eBay for $45.)

"Utah is the fry-sauce state," said Rula Katzourakis, who runs seven Crown Burger restaurants in the Salt Lake Valley with her family. She says she wouldn't dare open a restaurant here without fry sauce.

Slowly, though, Utah's title is fading. A more transient population, expanding businesses and the Internet have helped spread fry sauce.

Gary Roberts is president of Arctic Circle restaurants, which are the descendants of a local restaurant that claims to have invented fry sauce here in 1948. Since then, the hamburger chain has helped popularize it in and outside the state.

Roberts — who keeps his fry sauce recipe in a safe — says an Arctic Circle store in the Oregon beach town of Newport now goes through more than five gallons a day.

"In Washington, when we opened up our first store up there, probably 80 percent of requests were probably for tartar sauce. That's dropped to 10 percent. That balance is taken up by fry sauce," he said. "It's so good it's addictive."

Roberts now produces about 140,000 gallons of fry sauce each year for his 78 stores in nine states. His restaurants also sell about 18,000 bottles annually.

The leader in online sales is a local outfit called Some Dude's Fry Sauce.

"We've sent it to every state," said Some Dude's founder Mike Thompson, who also sells his sauce in stores in a dozen Western states. "We've sent it to Scotland, to England, to Afghanistan. We send a lot of stuff over to the troops."

All told, Some Dude's Fry Sauce sells about 204,000 16-ounce bottles each year.

And like Roberts, Thompson is finding that he sells more fry sauce in Oregon than Utah. In fact, Utah ranks third, after Washington state.

The basic recipe is simple — one part ketchup, two parts mayonnaise. Many restaurants then spike this with salt, spices, garlic, relish, horseradish, even pickle juice. It's mostly used for dunking fries, though some restaurants slather it on burgers.