Coat inside of Crockpot™ slow cooker with nonstick cooking spray. Place beef on large cutting board. Pound into 1/4-inch thickness; cut evenly into two pieces.
Combine bread, onion, cheese, garlic, 2 tablespoons oil, Italian seasoning, egg, salt and pepper in food processor or blender; pulse just until mixture is moistened but still chunky. Divide bread mixture evenly over steak pieces; roll tightly to enclose filling. Tie each with kitchen string to secure.
Heat remaining 1 tablespoon oil in large skillet over medium heat. Add steak rolls; cook and turn 6 minutes or until browned on all sides. Pour ½ cup pasta sauce into bottom of slow cooker; top with steak rolls. Top with remaining pasta sauce. Cover; cook on LOW 4 to 5 hours. Cut steak rolls evenly into 14 pieces. Serve over pasta, if desired. Garnish with parsley.