In a large serving bowl, combine the chopped English cucumber, chopped Roma tomatoes, thinly sliced red onion, and fresh chopped parsley.

In a separate small jar or bowl, whisk together the extra virgin olive oil, red wine vinegar, minced garlic, dried oregano, salt, and black pepper until well blended.

Pour the vinaigrette over the vegetables and toss gently to coat evenly.

Let the mixture sit at room temperature for 15 minutes before serving to allow the flavors to meld.