Dice the chicken breast into small, uniform bite-sized pieces.
Heat the olive oil in a large pot over medium heat and add the chicken, sautéing for 5 minutes until golden brown on all sides.
Add the diced yellow onion, red bell pepper, and celery to the pot, cooking for 5 minutes until the vegetables have softened and the onions are translucent.
Stir in the minced garlic, dried oregano, sea salt, and black pepper, cooking for 60 seconds until the spices are fragrant.
Pour in the chicken bone broth and the standard chicken broth, scraping the bottom of the pot to release any browned bits.
Add the dry brown lentils, dry white quinoa, and rinsed chickpeas to the liquid.
Bring the soup to a rolling boil, then immediately reduce the heat to low.
Cover the pot with a lid and simmer for 25-30 minutes until the lentils and quinoa are tender.
Remove from heat and let the soup sit for 2 minutes before serving warm in a large bowl.