In a large bowl, combine the diced cucumbers, tomatoes, red onion, and parsley.

In a separate small bowl, whisk together the olive oil, red wine vinegar, garlic powder, salt, and black pepper until well combined.

Pour the dressing over the vegetable mixture and toss gently to coat all the ingredients evenly.

Let the salad sit for about 10 minutes to allow the flavors to meld.

Serve chilled or at room temperature.