Cook the rotini pasta according to package instructions until al dente. Drain and rinse under cold water to cool. Set aside.
In a large mixing bowl, combine the diced cucumber, halved cherry tomatoes, and chopped red onion.
In a separate bowl, whisk together the mayonnaise, Greek yogurt, apple cider vinegar, garlic powder, dried dill, salt, and pepper until smooth.
Add the cooled pasta to the vegetable mixture, then pour the dressing over the top. Gently toss until everything is well coated.
Cover the salad and refrigerate for at least 30 minutes to allow the flavors to meld.
Before serving, give the salad a good stir and garnish with fresh parsley.