- Sauté the Aromatics: In a large Dutch oven or heavy-bottomed pot, heat the extra virgin olive oil over medium heat. Add the chopped leek, celery, and grated carrot. Sauté for 6-7 minutes, stirring occasionally, until the vegetables have softened and become fragrant. Add the minced garlic and cook for one minute more. 
- Cook the Chicken & Farro: Pour in the low-sodium chicken broth, then add the rinsed farro, the bay leaf, and a generous amount of black pepper. Submerge the whole chicken breasts into the broth. Bring the liquid to a gentle simmer, then reduce the heat to low, cover, and cook for 20-25 minutes, or until the chicken is cooked through and the farro is tender. 
- Shred the Chicken: Using tongs, carefully remove the cooked chicken breasts and transfer them to a cutting board. Allow the chicken to cool for a few minutes, then use two forks to shred the meat into bite-sized pieces. Set aside. Remove and discard the bay leaf from the pot. 
- Create the Lemon-Egg Emulsion: In a blender, combine the 3 large eggs, fresh lemon juice, and lemon zest. Ladle about 1 cup of the hot broth from the pot and add it to the blender. 
- Temper the Eggs: Seal the blender lid, remove the center cap, and cover the opening with a folded kitchen towel to allow steam to escape. Blend on low, gradually increasing to high, for about 30 seconds until the mixture is completely smooth, pale, and frothy. 
- Thicken the Soup: Ensure the soup in the pot is at a very low simmer, not boiling. Slowly pour the blended egg-lemon mixture back into the pot while whisking constantly. Continue to stir as the soup thickens for 2-3 minutes. It is crucial not to let the soup boil, as this will cause the eggs to curdle. 
- Combine and Serve: Stir the shredded chicken back into the thickened soup and allow it to heat through for another 2 minutes. Taste and adjust with more black pepper if needed. Ladle the soup into bowls and garnish generously with the fresh chopped herbs.