In a large bowl, combine the chopped tomatoes, Persian cucumbers, red onion, parsley, and mint.
In a separate small bowl, whisk together the olive oil, lime juice, sumac, salt, and pepper.
Pour the dressing over the salad ingredients in the large bowl.
Gently toss all the ingredients together until well coated with the dressing.
Taste, and adjust the seasonings if needed.
Let the salad sit for about 10-15 minutes to allow the flavors to meld together.
Serve the Shirazi Salad chilled as a refreshing side dish or accompaniment to grilled meats or kebabs.
Store leftovers in an airtight container in the fridge for up to 3-4 days. NOTE: The longer the salad sits, the soggier the veggies will get.