Bring a large pot of salted water to a boil and add rotini pasta. Cook according to package instructions until al dente, typically around 8–10 minutes. Drain and rinse under cold water.

Dice the cooked chicken breast and chop the romaine lettuce into ribbons. If using, halve the cherry tomatoes. Place all prepared ingredients in a large mixing bowl.

Add the cooled pasta to the bowl with chicken, romaine, and cherry tomatoes. Toss gently until combined.

Drizzle Caesar dressing over the salad mix and toss gently until well coated.

Sprinkle grated Parmesan cheese and season with salt and pepper. Toss again.

Add croutons just before serving and toss lightly to distribute them.

Chill in the refrigerator for 30 minutes to 1 hour before serving.