4 microwaveable sliders. Made with black beans, peppers, corn and more. The White Castle Slider you're holding is something really different: a patty made with black beans, peppers, corn, and more, served on our signature bun. You're on your way to (in our opinion) the best-tasting black bean slider in America! Enjoy! White Castle has been a family-run business since 1921. We're the home of The Original Slider, which you can get from our restaurants or the frozen aisle anytime the crave hits. So our delicious White Castle Black Bean Sliders come from a long line of great taste! To be sold only as 4-pack. Not for individual resale. For maximum freshness and enjoyment, these sandwiches have been wrapped in twin-packs. Recyclable where recycling facilities exist. If you have any questions or comments, write to us and attach this panel with the printed code for proof of purchase. www.whitecastle.com. Facebook. Twitter. Instagram.