1. Preheat oven to 400°F Lightly coat a baking sheet with sides with cooking spray.
2. Combine the provolone, olives and pepper in a small bowl.
3. Lightly beat the egg white with a fork in a medium bowl. Mix the breadcrumbs and salt in a shallow dish.
4. Cut a horizontal slit along the thin, long edge of a chicken breast half, nearly through to the opposite side. Open up each breast and place one-fourth of the cheese filling in the center. Close the breast over the filling, pressing the edges firmly together to seal. Repeat with remaining chicken breasts and filling. Hold each chicken breast half together and dip in egg white, then dredge in breadcrumbs. (Discard leftovers.).
5. Heat oil over in a large nonstick skillet medium-high heat. Add chicken and cook until browned on one side, about 2 minutes. Transfer chicken to the prepared baking sheet, browned-side up, and bake until it is no longer pink in the center or until an instant-read thermometer registers 170°F, about 20 minutes.