Rinse 1 cup of quinoa under cold water. In a saucepan, combine with 2 cups of water or vegetable broth. Bring to a boil, then reduce heat and simmer until the quinoa is fluffy (about 15 minutes). Let cool completely.
Chop the cucumbers, tomatoes, red onion, and herbs into bite-sized pieces.
In a small bowl, whisk together olive oil, lemon juice, minced garlic, salt, and black pepper. Add a dash of Dijon mustard or red wine vinegar if desired.
In a large bowl, mix the cooled quinoa with chopped vegetables, olives, and feta cheese. Pour the dressing on top and toss gently to combine.
Cover and refrigerate for at least 30 minutes before serving. This helps the flavors blend beautifully.
