KFC's new chicken sandwich is a huge success: It's selling twice as fast as the brand's other sandwiches did at launch

• KFC's chicken sandwich is selling twice as its other sandwiches did at their launch.
• Keeping up with demand has been the chain's "main challenge," parent company Yum Brands said.
• Popeyes, Chick-fil-A, and McDonald's are all competing with KFC in the chicken-sandwich wars.

Sales for KFC's new chicken sandwich are booming.

The fast-food brand said US customers were buying double as many of the sandwich, simply called the "KFC Chicken Sandwich," as they had of other sandwiches launched in the past. The new sandwich replaced the "Crispy Colonel," and KFC has also previously launched a Cheetos sandwich and a donut fried chicken sandwich.

"Our main challenge has been keeping up with that demand," David Gibbs, CEO of KFC's parent company Yum Brands, said at its earnings call Wednesday.

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The sandwich contains an extra-crispy quarter-pound of chicken breast filet, pickles, and the option of spicy sauce or mayo on a brioche bun. It launched across the US in late February.

"Customers are loving the product and coming back more frequently for it," Gibbs said.

He added that there had been a "general tightening" in domestic chicken supply, but KFC told CNN that the brand wouldn't run out of the sandwich any time soon.

The chicken sandwich wars show no signs of stopping

Popeyes was credited with starting the chicken sandwich wars in 2019, when its sandwich became an instant success following huge social-media buzz. It sold out just two weeks after launch, and the chain sold 250 million of the sandwiches within its first year of launch.

Fast-food and fast-casual chains have been quick to jump in on the booming demand for chicken sandwiches. As well as KFC, other brands including McDonald's, Burger King, and Smashburger all launched new chicken sandwiches during the pandemic.

Chick-fil-A is known as the home of the original chicken sandwich, and its recipe has changed little since its creation by the chain's founder in 1964, Insider's Erin McDowell reported.