Step 1

Using a sharp knife, cut chicken breasts from breastbone and detach chicken legs from carcass. In a large soup pot or Dutch oven, cover chicken breasts, legs, and carcass with stock. Add garlic, thyme, and bay leaf.

Step 2

Heat stock over medium-high heat until temperature reaches between 150 and 160°F (66 and 71°C) on an instant-read thermometer; adjust heat to maintain stock temperature in the 150–160°F range. It's okay if the temperature bounces around a little, but try to keep it above 150 and below 170°F (77°C). Cook until thickest part of chicken breasts registers 150°F on an instant-read thermometer, about 1 hour. Remove chicken breasts and set aside.

Step 3

Bring soup to a simmer and continue cooking for 1 hour longer, skimming as needed. Discard thyme sprigs and bay leaf. Remove all chicken from pot. Pull meat from bones, shredding it into bite-size pieces; discard skin and bones. If broth is cloudy, you can strain it through a fine-mesh strainer to clarify it.

Step 4

Return all chicken to pot except breast meat and return to a simmer. Add diced carrot, turnip, onion (or leek), parsnip, and celery and cook until just tender, about 10 minutes. Season with salt and pepper. Add minced fresh herbs and remove from heat. Dice chicken breasts and stir into soup along with any accumulated juices. Serve hot.