Place the chicken thighs in a large heavy-bottomed pot and sear over medium-high heat until golden brown on both sides, about 5 minutes per side. This creates a rich base for the soup.
Add chopped onion, sliced carrots, and sliced celery to the pot. Cook, stirring occasionally, until the vegetables are fragrant and slightly softened, about 8 minutes, filling your kitchen with a savory aroma.
Pour in water or chicken broth until the ingredients are fully submerged. Bring the mixture to a gentle boil over high heat, then reduce the heat to maintain a slow simmer.
Gently simmer the soup uncovered for about 45 minutes. Skim off any foam that rises to the surface with a slotted spoon to keep the broth clear and clean-tasting.
Remove the chicken thighs from the pot using tongs, then shred the meat with two forks until it’s tender and easy to pull apart. Discard the bones.
Return the shredded chicken to the pot, stirring to combine with the broth and vegetables for even flavor distribution.
Add chopped parsley, fresh thyme sprig, and lemon zest to the soup. Stir gently and cook for another 5 minutes to let the flavors meld.
Taste the broth and season with salt and pepper as needed. Adjust the seasoning to your liking for a balanced, bright flavor.
Let the soup rest for a few minutes, allowing the flavors to settle and intensify, then ladle into bowls.
Serve hot, perhaps with a slice of crusty bread, and enjoy the comforting, nourishing flavors of this homemade chicken soup.
