Place chicken in crockpot/slow cooker. In a bowl, stir together lime juice, chili powder, cumin, chicken broth, fire roasted tomatoes, and green salsa. Pour over chicken.

Cook frozen chicken on low for approximately 6 hours and thawed chicken on low for approximately 3-4 hours.

About half an hour before you're ready to serve it, remove chicken breasts to a plate, shred, then stir back into the sauce mixture in the crockpot. Let slow cook for about another half an hour so the flavors can come together and seep into the shredded chicken.

Scoop chicken mixture with a slotted spoon to allow most of the juices to run off or the tortillas will get soggy.

Serve shredded chicken in flour tortillas with shredded cheese, sour cream, diced tomatoes, salsa, lettuce, and cilantro for garnish. Squeeze fresh lime juice over each before serving, if desired.