Preheat your oven to 350°F (175°C).
In a small bowl, mix the melted butter, Dijon mustard, Worcestershire sauce, and poppy seeds.
Slice the slider buns in half horizontally and place the bottom halves in a baking dish.
Layer the ham evenly over the bottom half of the buns.
Add a layer of cheese over the ham.
Place the top halves of the buns on the cheese.
Brush the butter mixture over the tops of the buns.
Cover the dish with aluminum foil and bake for 15 minutes.
Remove the foil and bake for an additional 10 minutes, or until golden brown.
Let cool slightly before serving, then cut into individual sliders.