Cook the rotini pasta according to package instructions until al dente. Drain and rinse under cold water to cool.
In a large bowl, combine the cooked pasta, diced chicken, cherry tomatoes, and chopped romaine lettuce.
Drizzle the Caesar dressing over the pasta mixture and toss gently to combine.
Sprinkle in the grated Parmesan cheese, black pepper, and garlic powder, then toss again until evenly coated.
If desired, top with croutons for added crunch.
Chill in the refrigerator for at least 30 minutes before serving to allow flavors to meld.