1. Preheat oven to 350°.
2. Cook bacon in a large ovenproof skillet until crisp. Remove bacon, reserving drippings in pan; crumble bacon. Combine bacon, next 6 ingredients, and 1/4 teaspoon salt. Cut a 1-inch-wide slit into the thick end of each breast half; carefully cut down to the center of chicken to form a deep pocket. Divide cheese mixture evenly among pockets. Secure with wooden picks. Sprinkle chicken with 1/4 teaspoon salt and pepper.
3. Heat pan over medium-high heat. Add oil to drippings. Add chicken to pan; saute 4 minutes. Turn chicken over. Bake at 350° for 12 minutes; let stand for 5 minutes.