In 2017, two cousins with absolutely zero professional baking experience decided to open a cookie business together.

Now, Crumbl Cookies has more than 980 stores across the U.S., topping $1 billion in sales across all franchises while selling more than 300 million cookies in 2022, according to co-founders Jason McGowan and Sawyer Hemsley.

"I never imagined in my wildest dreams that we would do over $1 billion in sales," says McGowan, 43, who estimates he invested about $68,000 of his own money to get the business off the ground. (The company declined to share its 2023 sales, saying those figures are still being audited.)

Crumbl's rise began when McGowan, a former tech executive at companies like Ancestry.com and television guide app i.TV, decided to start a business with his cousin. When their first store opened in Logan, Utah, in 2017, Hemsley was still studying marketing at Utah State University.

"We just thought it was a fun side hustle," McGowan tells CNBC Make It.

McGowan and Hemsley had never baked professionally before, but they meticulously tested different cookie recipes and enlisted friends, family and strangers to taste-test them. They grew confident enough in a single recipe, Crumbl's signature chocolate-chip cookies, to build their first location around it.

From there, the co-founders' backgrounds in tech and marketing took over. The pair used social media to build a huge following "from the beginning," McGowan says. They take cues from the fashion industry, by organizing weekly "drops" where they announce new, limited-edition cookie flavors on TikTok.

"It creates that hype. It creates that excitement. And it also creates some scarcity, because you can only have that cookie for that week," McGowan says. Individual Crumbl cookies typically cost between $4 and $5 apiece, with the per-cookie price decreasing if you order packs of four, six or 12, according to the company's website.

Crumbl's social media following currently tops 16 million followers across platforms. It has become particularly popular on TikTok, with more than 7 million followers and a viral hashtag, "#TasteWeekly." TikTokers use it to post reviews, both positive and negative, of Crumbl's cookie flavor drops.

As a result of that hype, Crumbl has attracted plenty of franchising interest — and used it to open more than 600 new stores between 2022 and 2023. McGowan says the pace will probably slow going forward — though Crumbl does intend to expand internationally, including in the U.K.

Crumbl has also attracted copycats, it claimed in a pair of 2022 trademark infringement lawsuits. Both eventually resulted in settlements with undisclosed terms. "Just as any company would, Crumbl chose to protect its brand," says a company spokesperson.

Indeed, McGowan says one of his biggest lessons so far is that Crumbl's success is fairly easy to replicate.

"As I get older and as I build this company, I realize more and more that everything that we do is really just something that anyone can do," he says. "Whether you don't have a mixer yet, or you don't have a recipe for a cookie yet, you just get started."

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