Prepare chicken: Place whole chicken breasts in your crockpot then pour the salsa over each breast.
Cook: Cook anywhere from 1 1/2 to 2 hours on high or 4 hours on low, you don't want to cook it longer because it will start falling apart.
Preheat your oven to 425 F degrees.
Add Cheese: Transfer the chicken to a 9x13 inch baking dish. Spoon some of the leftover salsa over the chicken. Sprinkle each breast with cheese, about 1/4 cup of cheese for each breast.
Bake: Place the baking dish in the oven and bake for 15 minutes or until the cheese is golden brown and is bubbling.
It’s not really recommended to cook frozen chicken in the slow cooker as there’s risk of bacteria contaminating the meat before it reaches a safe temperature. I would thaw it out in the microwave first for a few minutes before actually adding it to the slow cooker.
Please keep in mind that nutritional information is a rough estimate and can vary greatly based on products used.