Add the chicken breasts (whole) and chicken thighs (if using them) to the base of the slow cooker. Pour the salsa verde over the top. Season with a little salt and pepper.
(If you slow cooker "runs hot" and has a tendency to dry out meat, you might want to add about 1/2 cup of water as well.)
Set on low and cook for 8 hours.
Once cooked, transfer the chicken pieces to stand mixer (or large bowl) and add 3/4 to 1 cup of the liquid from the slow cooker and mix until shredded to your preference. (If you don't have stand mixer, you can use 2 forks to shred the chicken in a larger bowl.)
Use to fix with favorite shredded chicken recipes.
Freezer Instructions: Freeze in plastic baggie or container. To thaw, place in bowl of warm water in the fridge and then reheat over low heat in large skillet with oil or water.