01 - Lay out bread slices and spread softened butter evenly on one side of each slice.
02 - Arrange two bread slices, buttered side down, on a clean surface. Evenly spread half the pizza sauce over each.
03 - Sprinkle half the shredded mozzarella over the sauce. Layer pepperoni slices evenly atop the cheese. Add olives if desired.
04 - Top each with the remaining mozzarella. Place the other bread slices on top, buttered side facing up.
05 - Heat a nonstick skillet over medium heat. Transfer sandwiches to the skillet and cook for 3–4 minutes per side, pressing gently, until bread is golden and cheese fully melted.
06 - Remove from skillet and let sandwiches rest for 1 minute. Slice in half, garnish with fresh basil or parsley and Parmesan cheese if using. Serve warm.