Add the onion, garlic, carrots, Italian seasoning, salt, tomato sauce, chickpeas, stock, and water to a 6-quart slow cooker, stirring to combine. Add the chicken and stir again.
Cover and cook on high for 3-4 hours, or low for 5-6, or until the veggies and chicken are cooked through..
Remove the chicken. Shred with two forks and set aside.
Add the corn, zucchini, and quinoa. Cover and continue to cook on high for an additional 30 minutes, or until the quinoa is cooked through.
Add back the shredded chicken, sprinkle with parsley and serve.