For vegetarian option omit the chicken and use chickpeas instead.
For the salad
Bring the water and garlic to a boil in a saucepan. Stir in the quinoa, reduce heat to medium-low, cover, and simmer until the quinoa is tender and the water has been absorbed, 15 to 20 minutes. Discard the garlic clove and scrape the quinoa into a large bowl.
Gently stir the chicken, onion, bell pepper, olives, feta cheese, herbs and salt into the quinoa.
Drizzle with the lemon juice, and vinegar, and olive oil. Stir until evenly mixed.
Serve warm or refrigerate and serve cold.