I just throw frozen chicken breasts in, add a jar of salsa, and cubed cream cheese. Cook on Low all day. Techically the recipe I read said to take the cream cheese and stir in with half the salsa. Put in the center of the chicken and roll it up. Place the rolls in the crock pot and dump the remaining salsa on the top. On Low you only have to cook for around 6 hours. I'm at work all day, so I go with frozen.
It makes the chicken fall apart so one night I'll put the chicken over rice and then the next day for lunch, I shred it for burritos. The cheese is soft but not part of the salsa unless you stir it up.