Place chicken in Crock Pot, and cook on HIGH for 3 hours or on LOW for 6 hours.
After 3 hours on HIGH or 6 hours on LOW, drain juices from Crock Pot.
Pour Pizza Sauce over chicken and sprinkle with Mozzarella Cheese.
Place 2 – 4 Pepperoni slices on each Chicken Breast and cook on HIGH for 30 minutes {covered}, or until done. Enjoy!