Rinse the quinoa thoroughly under cold water in a fine-mesh strainer to remove its natural bitter coating.

In a medium saucepan, combine the rinsed quinoa and water (or broth). Bring to a boil, then reduce heat to low, cover, and simmer for 15 minutes until the liquid is absorbed.

Remove from heat and let it sit covered for 5 minutes. Fluff with a fork and let it cool completely.

While the quinoa cools, whisk together the olive oil, lemon juice, minced garlic, dried oregano, salt, and pepper in a small bowl to make the dressing.

In a large serving bowl, combine the cooled quinoa, diced cucumber, cherry tomatoes, red onion, kalamata olives, feta cheese, and fresh parsley.

Pour the lemon vinaigrette over the salad and toss gently to combine.

Serve immediately, or cover and refrigerate for up to 4 days for meal prep.