Costa owned Costa’s Grocery in the Hill, a traditional Italian-American neighborhood where fire hydrants are still painted in the colors of the Italian flag. Provel was supposedly first used by a pizzeria called Luigi’s Restaurant in 1953, but got its big break when Ed Imo, the founder of Imo’s Pizza, first tasted the not-cheese cheese in the 1960s. He was so impressed that he made it Imo’s signature cheese when he and his wife Margie opened their first location in 1964. (It makes sense; the low melting point of Provel is perfect for pizza, leaving a luscious coating across the top, like a salty-velvety blanket.)

The first Imo’s was located in the Hill and eventually, with demand so high, Ed Imo bought Costa Grocery, which had the sole rights to sell Provel. Today, there are a hundred Imo’s stores across Missouri, Illinois, and Kansas, and Imo’s Food is the exclusive distributor of Provel, which is now manufactured and trademarked by a subsidiary of Kraft Heinz. And while pizza may have popularized Provel, now it’s everywhere in St. Louis: covering the chicken sandwich at local chain Syberg’s, subbed in for cheese curds in poutine and stuffed in avocado wraps at the Window Kitchen inside Third Wheel Brewing, and bubbling across the paninis and garlic bread at Guido’s.

Even though, according to Imo’s, millions of pounds of Provel are consumed each year, it’s difficult to find virtually anywhere else in the U.S. George Frasher, a proud St. Louis native, had to order in the cheese specially from Imo’s when he decided to put pizzas on his menu in Phoenix back in 1999. “I had Imo’s [Pizza] shipped out for me and I was sitting at the bar one night eating some,” Frasher remembers. “One of my regulars asked what it was, so I gave him a bite, and the next thing you know, it was on our menu.”

At the Smokehouse, Frasher only uses Provel for his handcrafted pizzas. The ingredient is so tricky to find that before he was able to import Provel directly from Imo’s, his mother would have to buy it from Roma Grocery in the Hill, drive to the airport, and ship it to Phoenix. But for a little taste of nostalgia, it’s worth it. “It’s the pizza I grew up on,” Frasher says. “It carries a special place in my heart and the Provel cheese is what does it.”

Not everyone loves Provel cheese as much as Ed Imo or George Frasher, though; we have friends in St. Louis who won’t touch it. The soft, gooey texture and tangy, smoky flavor combination plant it firmly in polarizing territory, but regardless of where you stand, if you say Provel, anyone from St. Louis knows what you’re talking about. “I feel it’s so unique and no one else has it here, so I try to utilize it on as many dishes as possible in my three restaurants [Frasher’s Smokehouse, Frashers Tavern, and Mrs. Chicken],” Frasher explains.

After I tried their pizza, I ordered my own block of Provel and a clamshell of thin, licorice-like Provel cheese ‘ropes’ through Imo’s Pizza (on Goldbelly) and found the ingredient to be pretty versatile. I scattered the pieces across a salad with salami and black olives, and it tasted similar to what you might find in any of the Italian restaurants in the Hill. Cold, the Provel hits different, with a flavor almost reminiscent of Gouda and a waxier texture than when melted over pizza. Slices from the block meld dreamily to the tops of charred burgers on the grill. And diced chunks create a thick, gooey coating for homemade macaroni and cheese.

It may be divisive, not a “real” cheese, and certainly not the fanciest ingredient on the shelf, but that’s part of why I love it. Just like slingers and Busch Stadium, it’s a little piece of St. Louis that connects me to my favorite person. Melt my heart, Provel.