Add the cold chicken broth, peppercorns, lemon, carrot, celery, onion, bay leaf, thyme, garlic, and chicken breasts to a medium saucepan.
4 cup chicken broth, 4 black peppercorns, 1 lemon, 1 carrot, 1 celery stalk, 1 small white onion, 1 bay leaf, 2 sprig fresh thyme, 2 clove garlic, 2 boneless