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 cooked pasta, cherry tomatoes, diced cucumber, and red onion.

In a separate bowl, whisk together the mayonnaise, sour cream, apple cider vinegar, garlic powder, oregano, salt, and pepper until smooth.

Pour the creamy dressing over the pasta and vegetables, and gently toss until everything is well coated.

Cover and refrigerate the salad for at least 30 minutes to allow the flavors to meld.

Before serving, give the salad a gentle toss and garnish with fresh basil leaves.