Some call Costco’s new burger ‘Shake Shack copycat’

Some Costco locations are serving up a new burger -- and it’s causing chatter beyond the food court. 

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Observations of the new burger have circulated for weeks, and it’s making headlines because food critics are comparing it to a Shake Shack burger.

Costco's new burger looks remarkably similar to Shake Shack’s https://t.co/rnQfFJTvNU pic.twitter.com/iSyyKiskbM

— Eater LA (@eaterla) May 26, 2017

Shake Shack, a popular chain that hasn’t made it to the northwest U.S., builds its burger with all-natural Angus beef, a “Chicago-style” potato bun, the Shack's sauce, which is made up of mayo, dijon mustard and dill pickle brine.

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“The final product looks nearly identical to Shack's beloved burger, though the ingredients are slightly different,” wrote Delish.com's Rheanna O’Neil Bellomo, who simply called it a “Shake Shack copycat.”

Costco's New Burger Looks Like A Shake Shack Copycat https://t.co/cFzEsBrrqQ pic.twitter.com/k525LyaCsS

— Delish.com (@DelishDotCom) May 25, 2017

Ingredients in the 1/3 pound Costco burger are reported to be an organic beef patty, topped with romaine lettuce, and smoke Thousand Island dressing.

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When the Seattle Times checked in with Costco Corporate about Seattle as a test market, it wouldn’t confirm the cheeseburger. But a reporter found one for sale at the Costco location in SoDo, costing a modest $4.99 and not-so-modest 1,140 calories.

According to Eater, the burger is in a localized testing phase.