Preheat oven to 375 degrees. Prepare a baking sheet with foil, and spray with non-stick cooking spray (this makes for easy clean up!) Lay chicken out on prepared baking sheet.
To make the stuffing, mix together mozzarella, pizza sauce, and seasonings in a small bowl.
Spread mixture out evenly over chicken breasts. Roll up each chicken breast, and place seam side down on baking sheet. Pour remaining pizza sauce over the top of the chicken breasts, and place 3 pepperonis on top of each chicken breast.
Bake for 30-35 min, or until chicken is cooked through, (when chicken is no longer pink in the middle).