Place chicken in a pot and cover with water or broth
Add salt, pepper, onion, garlic, and bay leaf if desired
Bring to a boil, then reduce to a simmer
Cook until the chicken reaches 165°F internal temperature
Simmer boneless chicken breasts for 15 to 20 minutes
Simmer bone-in chicken pieces for 25 to 40 minutes
Remove chicken from the pot
Let chicken cool slightly
Shred or chop the chicken
Return the chicken to the soup before serving