Heat a large soup pot over medium heat and add a tablespoon of olive oil. Once shimmering, add diced chicken and cook until lightly browned and opaque. Remove chicken and set aside.
Add chopped carrots, celery, and minced garlic to the same pot. Sauté for about 5 minutes, until vegetables become fragrant and slightly tender.
Pour in the chicken broth and bring the mixture to a gentle simmer. Add lemon or orange zest and chopped thyme for a bright, aromatic infusion. Let it simmer for 10 minutes to develop layered flavors.
While the broth simmers, cook the egg noodles in a separate pot according to package instructions until just tender. Drain quickly to prevent overcooking.
Add the cooked chicken back into the broth and stir in salt and pepper to taste. Let the soup simmer for another 5 minutes for all flavors to meld.
Stir in the cooked noodles and chopped fresh herbs, allowing the heat to warm them through and release their aroma. Adjust seasoning as needed.
Serve the hot soup in bowls, garnished with extra herbs if desired. The clear broth should be fragrant with citrus and herbs, with tender chicken and noodles providing a hearty texture.
