Gather all your ingredients to make the cooking process smoother.
Heat olive oil in a large pot over medium heat. Add diced onion and sauté for 3-4 minutes until translucent.
Add minced garlic and cook for an additional minute until fragrant. Then add chicken breasts and chicken broth, bringing to a gentle simmer.
Cook chicken for 15-20 minutes until fully cooked. Remove chicken, shred it, and return to the pot.
Add heavy cream, diced tomatoes, dried basil, dried oregano, salt, and black pepper. Stir well, then add sliced mushrooms, diced carrots, and diced celery. Simmer for another 10-15 minutes until vegetables are tender.
Stir in baby spinach and cook for an additional 2-3 minutes until wilted. Serve and garnish with fresh parsley.