Costco testing Shake Shack-style burger in Bay Area, Southern California

PACOIMA, Calif. -- Move over, Shake Shack. Costco is getting into the burger game.

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The bulk retailer has long been known for its cheap pizza and hot dogs, but the company has confirmed that it is expanding its in-store menu to include a burger with an organic beef patty and a not-quite-cut-through brioche bun that strongly resembles Shake Shack's coveted version.

Costco is testing the new burger in five California locations: Pacoima, Corona, Livermore, Folsom and Lakewood.

About a year ago, a Reddit user in Livermore posted a photo of a cheeseburger that was being sold at the Bay Area location's food court. But it appears that burger was on a different roll than the current Chicago-style bun.

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A corporate communications representative for Costco did not deny that the menu addition was their own take on Shake Shack's burger.

The burger, according to Orange County-based blog Foodbeast, will sell for $4.99. Shake Shack's single sells in Glendale for $5.55.