Boil a large pot of salted water over medium-high heat. Add the rotini pasta and cook according to package instructions, typically around 8–10 minutes, until al dente. Drain the pasta, rinse under cold water, and let cool completely in a colander.

In a large mixing bowl, combine the cooled rotini pasta with diced cucumber, grated carrot, chopped sweet onion, sliced kalamata olives, diced bell pepper, and chopped parsley. Gently fold to mix all ingredients.

In a mason jar, add Greek yogurt, red wine vinegar, lemon juice, minced garlic, onion powder, dried oregano, and chopped dill. Secure the lid and shake vigorously for about 30 seconds until well combined and creamy.

Pour the tzatziki dressing over the salad and gently toss to coat all ingredients.

Cover the salad and refrigerate for at least 1 hour before serving to allow flavors to meld.