Place chicken breasts in a pot with broth and bring to a boil over high heat. Turn heat to low, cover and simmer for about 15 to 20 minutes. Do not let the liquid boil off; add water if necessary. To test for if cooked, remove one chicken piece from the pot and cut it in half—thoroughly cooked meat will be white or light brown all the way through. Strain cooked chicken from pot and place on a cutting board; set aside remaining broth. Allow chicken to cool, then chop into small pieces.