Heat the large pot over medium heat and add the olive oil. Once shimmering, add the chopped onion and sauté until translucent and fragrant, about 3-4 minutes, stirring occasionally.
Add the minced garlic, diced carrots, and celery to the pot. Cook for another 2-3 minutes until the vegetables start to soften and the garlic smells fragrant.
Pour in the chicken broth and raise the heat to bring the mixture to a gentle boil. Stir occasionally and let it simmer for about 10 minutes, allowing the vegetables to become tender and flavors to meld.
Stir in the uncooked rice and dried thyme. Cover the pot and reduce the heat to low. Let simmer for 15 minutes, or until the rice is fluffy and tender, stirring occasionally to prevent sticking.
Add the shredded cooked chicken to the pot and stir well. Warm everything together for about 5 minutes until the chicken is heated through and flavors unite.
Taste the soup and season with salt and freshly ground pepper as needed. Adjust seasonings according to your preference. The soup should be creamy with visible rice and tender chicken pieces.
Serve hot, garnished with freshly chopped parsley for a pop of color and freshness. Enjoy the cozy, seasonally inspired flavors with a slice of crusty bread if desired!
