White Castle has become the first nationwide fast-food chain to offer a plant-based, meat-free Impossible Burger.

After a trial period at a few select locations, the slider joint rolled out the Impossible Slider nationwide Wednesday at all 377 restaurants. The vegetarian slider is served with smoked cheddar cheese, pickles and onions and is $1.99.

White Castle CEO Lisa Ingram said in a news release that sales “easily exceeded our expectations” in the pilot run.

“The Impossible Sider is a hit with both loyal ‘cravers’ and customers brand new to White Castle who are seeking out this buzz-worthy slider.”

Impossible Foods makes their burgers without hormones, antibiotics or artificial flavors. They are cholesterol-free but not low-fat because they’re made with coconut fat. Impossible Foods also uses heme, an iron-containing molecule found in meat and soy. The company genetically engineers yeast to make the heme used in their products.

A White Castle in Dearborn had sold four Impossible Sliders at 1 p.m. Wednesday, a worker said.

Kimberly Mallory, vegetarian from Lake Orion, tried the slider and said it was better than she expected.

“It’s actually pretty good,” said Mallory, 60. “Needs some ketchup, but otherwise, I like the taste. It’s seasoned well, has that meat texture and the bun is soft.”

Justus Aguinaga, 21, also tried the slider after having a Shake Shack burger in Campus Martius on Wednesday.

“I think it tastes true to White Castle’s original sliders,” said Aguinaga of Macomb County. “I’d even put it up next to a Shake Shack burger. I could eat a bunch of these for the price.”

Downtown Detroit’s Central Kitchen + Bar at 660 Woodward also announced this month is using Impossible Foods. Owner Dennis Archer Jr. and his team have launched a new menu of plant-based foods, including a unique take on the Impossible Burger.

mbaetens@detroitnews.com

Twitter: @melodybaetens

