Prepare the greens by washing and drying the romaine lettuce thoroughly.

Chop the cucumber and halve the cherry tomatoes. Thinly slice the red onion.

In a small bowl, whisk together red wine vinegar, olive oil, Dijon mustard, honey, salt, and pepper until emulsified.

In a large mixing bowl, combine the lettuce, cucumber, tomatoes, olives, mozzarella balls, red onion slices, and basil leaves. Drizzle half of the vinaigrette over the top.

Toss gently until everything is coated in dressing. Adjust seasoning if needed.

Serve immediately for optimal freshness.