Start the vinaigrette. In a small bowl, combine the olive oil, lemon juice, champagne vinegar, garlic, Dijon mustard, salt, and pepper. With a whisk, stir the mixture until emulsified.

Place the cooked quinoa in a large mixing blow and drizzle with half of the dressing. Add the tomatoes, peppers, cucumbers, Kalamata olives, chickpeas, and green onions. Toss together with the remaining dressing.

To finish the salad, at the feta cheese and the herbs. Toss all together, taste for seasonings, and add more if desired. If desired, add a sprinkle of red pepper flakes and gently mix.