Preheat the oven to 350º F.

Slice the Hawaiian Sweet Rolls in half (keep the rolls attached and use a serrated knife to carefully slice horizontally, to make a top and a bottom half of the rolls).

Place the bottom half of the rolls on a baking sheet.

Spread a layer of yellow mustard on the bottom half of the rolls.

Layer on the pastrami slices, folding the slices into thirds as you lay them on.

Then, top the pastrami layer with the Swiss cheese slices.

Top each slicer with one or two dill pickle chips. 

Place the top half of the Hawaiian Sweet Rolls on top.

Melt the butter and onions on the stovetop or in the microwave. Stir in the garlic powder.

Brush or drizzle the melted butter onion mixture over the tops of the sliders. 

Cover the Slicers with foil and bake about 20 minutes. 

Uncover sprinkle the top with Everything But the Bagel Seasoning, if using. Bake for an additional 6 minutes, until the tops are golden brown. Let cool about 5 minutes, then use a serrated knife to separate each slider.