Place the chicken thighs in a large heavy-bottomed pot and cover with water or chicken stock. Bring to a gentle simmer over medium heat, creating a fragrant aroma as the broth begins to develop.
While the broth simmers, chop the onion, carrots, and celery into even pieces, and mince the garlic. Set aside for the next step.
In a separate pan, heat olive oil over medium heat. Add the chopped onion and garlic, sautéing until fragrant and just beginning to turn golden, about 3 minutes.
Transfer the sautéed aromatics into the simmering broth, along with the chopped carrots and celery. Continue to simmer uncovered for about 45 minutes, skimming off any foam that rises to keep the broth clear.
Once the chicken is tender and falling apart, remove it from the pot using a slotted spoon. Shred the meat with two forks, discarding bones, and return the shredded chicken to the pot.
Add a splash of lemon juice to the broth for brightness. Let everything simmer for another 15 minutes until the vegetables are soft but not mushy.
Taste and adjust seasoning with salt and pepper as needed. Stir in chopped fresh herbs for a burst of herbal freshness.
Serve the soup hot, with tender shredded chicken, soft vegetables, and a clear, aromatic broth, perfect for cozy evenings.
