Chop romaine into bite-sized pieces and place in a large bowl.
Prep all vegetables by halving tomatoes, dicing cucumber and bell pepper, and thinly slicing red onion.
Cube mozzarella, slice salami, olives, and banana peppers, and chop fresh herbs.
Blend olive oil, red wine vinegar, garlic, Dijon, lemon juice, oregano, salt, pepper, and sugar with an immersion blender until smooth.
Layer or toss all salad ingredients together in a serving bowl.
Drizzle dressing over salad just before serving, or serve on the side.