Cook the Pasta: Begin by bringing a large pot of salted water to a boil. Add the rotini pasta and cook according to package instructions until al dente, usually about 8-10 minutes. Once cooked, drain in a colander and rinse under cold water to stop the cooking process.

Combine Dressing and Cheese: In a large mixing bowl, combine the cooled rotini pasta with your choice of Italian dressing and grated Parmesan cheese. Stir gently to ensure the pasta is evenly coated.

Add the Vegetables: Fold in the diced red and green bell peppers, finely chopped red onion, grated carrot, halved cherry tomatoes, and sliced black olives. Gently mix until well incorporated.

Incorporate the Cheese: Carefully add the cubed mozzarella cheese to the pasta salad, mixing just enough to blend the cheese with the ingredients without crushing it.

Season the Salad: Sprinkle Italian seasoning, and season with salt and pepper to taste. Mix gently to incorporate these seasonings throughout the salad.

Chill to Meld Flavors: Cover the salad and refrigerate for at least 1 hour, allowing the flavors to meld beautifully.

Final Toss and Garnish: Before serving, give the salad a gentle toss and garnish with freshly chopped parsley.