Preheat a grill pan or large nonstick griddle over medium to medium high heat. Build your sandwiches: place 2 or 3 slices of prosciutto on 1 piece of bread. Top with an even layer of roasted pepper and an even layer of sliced mozzarella, top with another slice of bread. Drizzle the tops of your assembled sandwiches with extra-virgin olive oil. Place the olive oil coated bread face down on the grill or griddle and drizzle the opposite side with additional extra-virgin olive oil. Weight the sandwiches down with a tin foil covered brick or a heavy skillet filled with a sack of flour or heavy canned goods. Press the sandwiches 2 or 3 minutes on each side, then serve immediately.