Gather all your ingredients and chop the onions, carrots, and celery into bite-sized pieces. Zest and juice the lemon, and set everything nearby for easy access.
Heat the heavy-bottomed pot over medium heat and add a splash of olive oil until shimmering. Sauté the chopped onions, carrots, and celery until they soften and release a sweet aroma, about 8 minutes. Stir occasionally to prevent sticking.
Push the vegetables to the sides of the pot and add the chicken pieces, skin side down. Brown them for about 5-7 minutes until golden and slightly crispy, then flip to brown the other side.
Pour enough water or broth into the pot to fully cover the ingredients. Bring to a gentle simmer, just below bubbling, at about 90°C / 194°F. Skim off any foam that rises to keep the broth clear.
Lower the heat and let the soup simmer gently for 1.5 to 2 hours. This slow cooking develops rich flavors and tender chicken that starts to fall apart.
Carefully remove the chicken from the pot. Shred the meat into bite-sized pieces, discarding the bones, and return the shredded chicken to the broth. Stir gently to combine.
Add the lemon juice and zest to the soup, and season with salt and freshly ground black pepper to taste. Stir well, allowing the bright citrus to lift the flavors.
Let the soup rest for 10 minutes, allowing the flavors to meld. Taste again and adjust seasoning if needed.
Serve the hot soup in bowls, garnished with fresh herbs for a fragrant finish. Enjoy the comforting, vibrant flavors with a slice of crusty bread if desired.
