Rinse the quinoa under cold water using a fine-mesh strainer. In a medium saucepan, combine the quinoa with 2 cups of water. Bring to a boil, then reduce heat to low, cover, and simmer for about 15 minutes or until the water is absorbed and the quinoa is fluffy.
While the quinoa is cooking, prepare your vegetables. Dice the cucumber, halve the cherry tomatoes, slice the olives, and finely dice the red onion.
In a small bowl, whisk together the olive oil, lemon juice, minced garlic, salt, and pepper to create the dressing.
Once the quinoa is cooked, fluff it with a fork and let it cool for about 5 minutes.
In a large bowl, combine the cooled quinoa, cucumber, tomatoes, feta cheese, olives, and red onion.
Pour the dressing over the salad and gently toss to combine.
Sprinkle the chopped mint and parsley over the salad and give it one final gentle toss.
Taste and adjust seasoning if needed. Serve immediately or chill in the refrigerator for an hour to let the flavors meld together.