Cook the rotini pasta according to package instructions until al dente. Drain and rinse under cold water to cool.

In a large mixing bowl, combine the cooled pasta, cherry tomatoes, cucumber, bell pepper, red onion, and black olives.

In a small bowl, whisk together the Italian dressing, dried oregano, salt, and pepper.

Pour the dressing over the pasta salad and toss gently to combine.

If using, sprinkle the feta cheese on top and give it a light toss.

Cover the salad and refrigerate for at least 30 minutes to allow the flavors to meld. Serve chilled or at room temperature.