Prepare the dressing by combining the Italian dressing mix, olive oil, white vinegar, water, mayo, Dijon mustard, and sugar in a medium-sized jar. Shake until well emulsified.

Wash and pat dry the salad ingredients. Slice the Roma tomatoes, thinly slice the red onions, and julienne the carrots.

In a large mixing bowl, layer the lettuce, red cabbage, carrots, red onions, black olives, tomato wedges, and pepperoncinis. Toss gently to combine.

Drizzle the prepared dressing over the salad and toss again until all ingredients are coated.

Sprinkle croutons and freshly grated Parmesan cheese over the salad just before serving.

Serve the salad immediately for the best experience.