The Impossible Slider Debuts at White Castle

On April 12, 2018, White Castle began selling the Impossible Slider at 140 of its restaurants across New York, New Jersey, and Chicagoland, the first time a major American fast-food chain put a plant-based burger on a permanent test menu. The patty came from Impossible Foods, the California startup known for a soy-based burger built to bleed and brown like beef, but the choice of test partner was the real story: White Castle had introduced the hamburger to mass America back in 1921 and was still family-owned. The slider sold for $1.99, topped with smoked cheddar, pickles, and onion on White Castle's own small bun. Sales came in well above what the chain had forecast, and by September 2018 White Castle had rolled the Impossible Slider out to nearly all 400 of its restaurants nationwide.