01 - Preheat your oven to 350°F (175°C).
02 - In a medium saucepan, combine the root beer, brown sugar, Dijon mustard, apple cider vinegar, and black pepper. Bring the mixture to a rolling boil.
03 - Reduce the heat to low and let the glaze simmer for 12–15 minutes, or until it has thickened and reduced by half, achieving a syrupy consistency. Stir in 1 tablespoon of butter until fully melted.
04 - Add the ham slices to the simmering glaze. Allow them to simmer for 5 minutes, turning halfway through to ensure even coating. Remove the glazed ham from the heat.
05 - Arrange the bottom halves of the slider buns in a 9x13-inch (23x33 cm) baking dish. If using, spread a thin layer of mayonnaise on the bottom buns.
06 - Evenly distribute the glazed ham slices over the bottom buns. Place a half-slice of Swiss cheese on top of the ham, followed by the dill pickle chips.
07 - Position the top halves of the slider buns over the layered ingredients. Brush the tops of the buns with the melted butter.
08 - Cover the baking dish with aluminum foil. Bake in the preheated oven for 15 minutes. Remove the foil and continue baking for an additional 5 minutes, or until the cheese is fully melted and the buns are golden brown.
09 - Remove the sliders from the oven. If desired, sprinkle with chopped fresh parsley for garnish. Serve the sliders warm.