Warm the olive oil in a large pot over medium heat; add the onion, carrots, and celery, cooking gently until the onion is translucent and veggies start to soften, about 6 to 8 minutes.
Stir in the garlic, thyme, oregano, and turmeric, moving constantly for one minute until the spices release their aroma without burning the garlic.
Pour the chicken broth into the pot, scraping the bottom to lift any browned bits; then add the diced potatoes, whole chicken breasts, and bay leaf.
Bring the mixture up to a boil, then lower the heat to maintain a gentle simmer; cover and cook for 20 to 25 minutes until the potatoes are tender and chicken is cooked through.
Take out the chicken and bay leaf; shred the chicken with forks and return it to the pot. Optionally, stir in spinach or frozen peas and cook for 2 minutes until wilted.
Remove the pot from heat and mix in the fresh lemon juice. Season with salt and pepper to taste, garnish with parsley, and serve warm.