Preheat oven to 350°F (175°C).
Slice slider buns in half horizontally, keeping them attached.
Place the bottom halves in a baking dish.
Layer ham, Swiss cheese, and pickles over the buns.
Place the top halves of the buns over the filling.
In a bowl, mix melted butter, Dijon mustard, Worcestershire sauce, and garlic powder.
Brush the butter mixture over the sliders and sprinkle with poppy seeds.
Cover with foil and bake for 15 minutes.
Remove foil and bake for another 5 minutes until golden brown.
Serve warm and enjoy!