In a large bowl, combine the chopped romaine lettuce, cherry tomatoes, cucumber, bell pepper, red onion, black olives, salami, mozzarella cheese, and parsley. Toss gently to mix the ingredients evenly.
In a small bowl, whisk together the olive oil, red wine vinegar, dried oregano, salt, and pepper until well combined.
Pour the dressing over the salad and toss again until all the ingredients are coated.
Sprinkle the grated Parmesan cheese on top before serving.
For best flavor, let the salad sit for about 10 minutes before serving to allow the flavors to meld.