One of the easiest recipes for a frozen chicken breast is to place it in a crock pot, cover with salsa, and cook it! That is really all it takes. A couple hours on low and you go from freezer to table with LITTLE effort.
I suggest using one of these crock pot liners for easy clean up, situate that on the crock pot first. You can add in 2 tablespoons of water or chicken broth to keep the chicken moist.
Add the frozen chicken breast to the bottom of the crock pot. Pour on the salsa and the seasonings, giving it a little stir.
Place the lid on the crock pot and cook on low for 2.5 to 3 hours. If using fresh chicken, cook for 1.5 to 2 hours. When the chicken has thawed enough (1.5 to 2 hours), I like to put in a meat thermometer to monitor the chicken. Make sure the chicken is fully cooked before removing it from the crock pot.
I like to shred my chicken (using a hand mixer) and use it in tacos, rice bowls or salads. Then, I will add it back into the salsa in the crock pot. to allow all the juices to absorb into the chicken. However, you can eat it whole or cut into slices.