There are few better ways to dress up a green grape than to dip it in caramel or white chocolate and coat the sticky orb in crunchy peanuts. If you’re from Chicago — the South Side, in particular — you probably know this. In recent years, these slightly tart treats known as taffy grapes have become an unstoppable trend, finding their way onto the menus of many local fast food restaurants.

One common location: Harold’s Chicken Shacks, where customers often order a plate of fried bird with a side of green candied, seedless grapes.

As Lanita Glover puts it, the decorated fruits are a “uniquely Chicago thing.”

A manager at the Harold’s in West Loop, Glover says taffy grapes rose to fame the same way the company’s crispy chicken and mild sauce did: by word of mouth. About a third of the people who phone her establishment are asking about the grapes.

“As soon as we get them in, they’re gone,” Glover says. “They’re one of the hottest desserts that we have. People order at least three to four cases.” (A case typically includes 20 to 30 grapes, each carefully hand-dipped.)

Not every Harold’s offers taffy grapes; it’s up to the owner to decide whether or not to stock them. Many of the chicken shacks that do, though, source them from Original Taffy Gourmet Grapes, a small Hyde Park operation. It’s run by Tonique Ware, who claims she’s one of the earliest taffy grape vendors.

The exact origin of the recipe remains a mystery, but Ware recalls first hearing about it in 2014. She started selling individual cups of grapes at parks and beaches, but demand grew so much she turned the hobby into a full-time job.

In 2015, Ware started working with Harold’s Chicken Shack No. 55 near the Dan Ryan, “and it just exploded from there,” she says. “Everyone wanted the grape. We were getting so many calls.”

Today, most of her clients are Harold’s outposts, where they are nearly as popular as wings and fries.

“They’re refreshing, they’re good, it’s an easy snack to pop in your mouth,” Glover says. “Who doesn’t like caramel, nuts, and grape?”