To make the tomato-cucumber salad: In a large bowl, combine all ingredients for the salad: tomato, cucumber, red onion, parsley, and cilantro. Sprinkle with salt and pepper and toss to combine.
To prepare the dressing, throw all of the dressing ingredients into a small bowl or a mason jar and whisk together vigorously, until well blended.
Pour the dressing over the veggies and toss gently. Cover the bowl with plastic and let sit at room temperature until ready to serve, for 1 to 3 hours. This will allow the flavors to come together.
Serve and enjoy!