Preheat oven to 375°F (190°C).
If using raw chicken, set up a breading station: one bowl of flour, one with beaten eggs, one with breadcrumbs mixed with Italian seasoning, garlic powder, and parmesan cheese.
Coat chicken: dredge each piece in flour, dip in eggs, then coat in breadcrumbs.
Place breaded chicken on a parchment-lined baking sheet and bake for 20 minutes, flipping halfway through.
Slice slider buns in half and place the bottoms in a baking dish.
Top each bun with a cooked chicken piece, spoonful of marinara sauce, and slice or sprinkle of mozzarella.
Add the bun tops. Brush with melted butter.
Bake assembled sliders for 10 minutes, or until cheese is melted and buns are golden.
Garnish with fresh basil, black olives, or edible eyes for a spooky look.
Insert toothpicks to hold sliders together if needed. Serve warm.