Bring a large pot of salted water to a boil. Add the cauliflower florets and blanch for about 3 minutes until just tender. Drain and immediately transfer to a bowl of ice water to stop the cooking process. Let cool for 5 minutes, then drain again and pat dry.
In a large mixing bowl, combine the cooled cauliflower, cherry tomatoes, red onion, olives, and parsley.
In a separate small bowl, whisk together the olive oil, red wine vinegar, oregano, garlic powder, salt, and pepper.
Pour the dressing over the salad and toss gently to combine.
Cover the salad and refrigerate for at least 30 minutes to allow the flavors to meld. Serve chilled or at room temperature.