Warm the olive oil in a large heavy pot over medium heat, then add the diced onion, sliced carrots, and celery. Cook gently for about 6 to 8 minutes until the onions are soft and clear, which forms a flavorful base for the soup.
Add the minced garlic along with the thyme, oregano, and turmeric. Keep stirring for about a minute until the herbs release their fragrance, taking care not to burn the garlic.
Pour in the chicken broth and use a wooden spoon to scrape any tasty bits stuck to the pot. Toss in the diced potatoes, place the chicken breasts whole into the pot, and add the bay leaf. Make sure the chicken is covered by liquid, adding a small amount of water if necessary.
Raise the heat to bring everything to a boil, then lower to a gentle simmer. Cover the pot and let the soup cook for 20 to 25 minutes until the potatoes are tender and the chicken reaches an internal temperature of 165°F.
Take the chicken and bay leaf out of the pot carefully. Shred the chicken finely using two forks, then return the shredded meat to the simmering soup. If desired, fold in spinach or frozen peas now and let them soften for about 2 minutes.
Turn off the heat, then stir in the freshly squeezed lemon juice to brighten the flavors. Season with salt and pepper to your taste. Sprinkle with chopped parsley just before serving, and enjoy your warm bowl of homemade comfort.
