Post vs. Post: The Real-Life Breakfast Betrayal Behind ‘Unfrosted,’ Netflix’s Pop-Tarts Movie

Thanks to the success of the NBC sitcom Seinfeld, Jerry Seinfeld has never seemed in a particular hurry to star in a live-action feature film. Instead, he has opted for cameos (like in 1996’s Eddie), animation (2007’s Bee Movie), and documentaries (2002’s Comedian). All that will change on May 3, when Seinfeld stars in Unfrosted, a Netflix original film that he also co-wrote and directed.

The premise that brought Seinfeld out of his seemingly self-imposed film exile: the origin of Pop-Tarts, the sugar-frosted pastry that first hit shelves in 1964.

It’s reasonable that Seinfeld will take some creative license with how the breakfast pastry came to be. On the other hand, the facts may not require much embellishment. It’s a story of warring cereal companies, a premature announcement, and a race to become the first processed and ready-to-be-toasted delicacy to arrive on kitchen tables.

A Tasty Problem

Postwar America was a good time to be in the cereal business. With more women entering the workforce and parents working longer hours, leisurely breakfasts were difficult to prepare and enjoy. Pouring cereal and milk into a bowl took only a few seconds.

By the early 1960s, the undisputed giant of the industry was Kellogg’s. The company behind Corn Flakes, Frosted Flakes, Corn Pops, Rice Krispies, and other hit cereals held 44 percent of the market—more than that of its two biggest rivals, Post and General Mills, combined. Both Kellogg’s and Post were based out of Battle Creek, Michigan, with each keeping a watchful eye on what the other was doing.

Post, which offered Alpha-Bits, Grape-Nuts, and All-Bran, wanted to secure more breakfast time with consumers. In 1963, company executives believed they had found a solution by building on a packaging method originated by dog food specialist Clarence Gaines, who had found a way to keep wet pet food moist in foil and not in a can.

Post, which had acquired Gaines’s company, discovered that it was feasible to offer a shelf-stable, fruit-filled pastry treat that could be heated and served. (For human consumption, naturally.) The product could be kept slightly moist so it wouldn’t dry out; bacteria and mold would be kept at bay. In food industry terms, they were “intermediate moisture foods,” a category that would grow to include granola bars, pie crusts, and military rations.

Post dubbed the pastry Country Squares. Executives were so excited that they made a product announcement in 1963—well before they were ready to distribute the product nationally. Instead, Country Squares were offered to media members and consumers in select test markets in Seattle, Minneapolis, and other cities, with Post figuring they had enough time to tweak the product until they were satisfied.

The company hyped them up as “little tartlets” that came out “piping hot.” Flavors included grape, strawberry, blueberry, and orange pineapple, all of which offered “a fourth of an adult’s daily minimum of six essential vitamins.”

In a highly competitive cereal market, showing your hand was foolhardy. When Kellogg’s chairman William LaMothe got wind of Country Squares, he immediately directed his staff to create a competing pastry and get it to market as quickly as possible. Thus began the breakfast equivalent of the space race, with two food giants looking to be the first to go beyond what was previously considered possible.

A Tale of Two Posts

Though they were experts in cold cereals, Kellogg’s had few resources to experiment with toasted and processed pastries. For help, they turned to another Post: Bill Post, an Army Air Force veteran and longtime food manufacturing specialist who ran a plant for the Hekman Biscuit Company (which later became Keebler) in Grand Rapids, Michigan. (For simplicity’s sake, we’ll refer to the Post company as Post Cereal and Bill Post as Post.)

In Post’s telling, he got a call and then a visit from Kellogg’s executives who wanted to do a shelf-stable pastry item but weren’t quite sure how. All they had, Post recalled, was some dough and filling to show him.

“In 1964 I answered the telephone and Kellogg asked if they could come see some of our equipment,” Post told WWMT in 2021. “I said, ‘Yeah.’ They came and looked at our plant … They said they wanted something for the toaster but they didn’t know how to do it.”

Post set about figuring out the logistics of mass-producing the product. In order to make the pastries, he needed two large sheets of dough that would sandwich a layer of fruit filling. To make those in large quantities meant constructing a 60-ton pressing machine.

“There were so many naysayers,” Post said. “Some of my good friends would say, ‘I don’t know, Bill.’ They would tell us it’s not such a good idea.”

Post also needed to formalize a recipe. Over the course of several months, he took samples home to his children, who would give him feedback on both flavor and texture. Eventually, Kellogg’s settled on four varieties: blueberry, strawberry, brown sugar cinnamon, and apple currant.

As Post Cereal continued to dither with Country Squares, Kellogg’s and Post moved quickly with their own product. They dubbed them Fruit Scones, and in just six months, they were ready for a regional rollout in Cleveland.

Tart Blanche

Kellogg’s still had issues to iron out. The prototype Fruit Scones had round, not square, corners: Eliminating the curve saved money. Like Post Cereal, Kellogg’s also assumed busy adults would be their target audience. But in testing the product, they realized that the toasted fruit pastry was more appealing to kids: Adults actually disliked it. Marketing was adjusted, and Kellogg’s gave the pastry a new name: Pop-Tarts, taken from the pop art movement of the 1960s and because the confections popped out of the toaster.

Kellogg’s introduced Pop-Tarts nationwide in 1965, beating Post Cereal to the punch and causing one Post Cereal employee to grouse that Country Squares were all but finished. (Not even a rebrand, to Toast ‘Em Pop Ups, helped.) Kellogg’s upped orders from 10,000 cases to 45,000 and still sold through them all, forcing the company to take out ads to apologize for the reduced inventory.

But Post wasn’t quite done innovating. In 1967, he developed a frosting for Pop-Tarts that would remain solid after heating using an icing machine meant for cookies. By 1968, Pop-Tarts had sprinkles. By 1974, they had their own advertising mascot, Milton the Toaster. Breakfast pastries were soon a $45 million market, with Kellogg’s controlling most of it.

Post went on to work for Kellogg’s as a consultant and fielded the occasional questions from journalists. After retirement, he was prone to take in some Pop-Tarts to share with his senior’s group. When he died in February 2024 at age 96, he was celebrated as one of the innovators behind the pastry. (While Post is widely credited with developing the Pop-Tart, Kellogg’s credits employee Joe “Doc” Thompson and their own in-house “kitchen crew” with its development, offering that Post “played an important role in co-creating” it; Post himself said that he had numerous people helping him.)

The Pop-Tart has also gone beyond breakfast tables. They’re a staple of military rations and have even been used as a way to render humanitarian aid to war-torn countries. When Somali pirates took over the Maersk Alabama cargo vessel in 2009—a story told in the Oscar-nominated film Captain Phillips with Tom Hanks—officials negotiated with them using chocolate Pop-Tarts.

The Pop-Tart has endured, though not without controversy. In 1993, it was reported that Pop-Tarts left in the toaster too long could catch fire, likely due to overheated corn syrup.

The story was picked up by national humor columnist Dave Barry, who conducted his own experiment after consulting with fire department officials in Dover, Ohio. They had simulated a Pop-Tart fire hazard to investigate a kitchen blaze alleged to be caused by an incendiary tart. Both the Dover fire inspectors and Barry arrived at the same conclusion: Forcibly holding down a Pop-Tart in a toaster in excess of five minutes could result in calamity. If any ripped-from-the-headlines fact is sure to make it into Unfrosted, it’s probably going to be the sight of a Pop-Tart bursting into flames.

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