Preheat the broiler. Split the rolls, then toast them under the broiler for 3 minutes until lightly golden.

Meanwhile, preheat a large skillet to medium-high heat with the butter. Add the beef, worcestershire, and seasoned salt in one even layer - you may need to cook the meat in batches. Let the beef brown and cook for 3 - 5 minutes until no longer pink on the edges, then remove to a plate to rest.

In the same pan with all the meat drippings, add the sliced bell pepper and cook for 3 - 5 minutes until soft and slightly charred. Add the beef back into the pan to combine with the bell pepper. Turn off the skillet.

To assemble, spoon a bit of the beef mixture into each slider bun. Top with a piece of cheese. Broil for 2 more minutes until the cheese is just melted, then top with jalapeno slices right before serving.