Heat the oven to 350°F and line a 9-by-13-inch baking pan with parchment. Split the connected Hawaiian rolls horizontally.
Place the bottom slab in the pan and layer on half the provolone, salami and capicola. Chop the pepperoncini into short pieces and scatter over the meat with the dry roasted pepper strips.
Add remaining provolone and the top slab. Mix butter, oregano and garlic powder and brush over the tops.
Cover with foil and bake for 15 minutes. Uncover and bake for 8 to 10 minutes until the cheese melts and the center reaches 165°F.
Rest for 5 minutes and cut into 12 sliders.