Rinse the quinoa under cold water. Add it to a pot with 2 cups of water and bring to a boil.
Reduce the heat to low, cover, and simmer for 15 minutes until the water is absorbed. Fluff with a fork and spread it on a tray to cool completely.
While the quinoa cools, whisk the olive oil, lemon juice, Dijon, garlic, salt, and pepper in a small bowl until smooth.
In a large bowl, combine the cooled quinoa, chicken, chickpeas, tomatoes, cucumber, bell pepper, carrots, red onion, and parsley.
Divide the mix evenly into 4 airtight containers. Do not add dressing yet.
Pour the dressing into 4 small leak-proof containers, or layer it at the bottom of mason jars if you prefer jar-style bowls.
Top each bowl with feta. Refrigerate right away.
When you're ready to eat, drizzle on the dressing, toss gently, and top with fresh sliced avocado.