Rinse the quinoa thoroughly under cold water. Combine quinoa and water in a saucepan and bring to a boil.

While the quinoa is cooking, chop the cucumber, halve the cherry tomatoes, finely chop the red onion, and chop the fresh parsley.

Once the quinoa is cooked and cooled, combine it with the prepared vegetables in a large bowl. In a separate small bowl, whisk together olive oil, lemon juice, salt, and pepper for the dressing.

Pour the dressing over the quinoa and vegetable mixture, then toss gently to combine everything. Serve immediately or chill for later enjoyment.