Place chicken in a slow cooker with chicken stock. Cover and cook on low heat for 4-6 hours or high for 2 to 3 hours. Remove liquid from slowcooker. Use two forks to shred chicken. Pour enough dressing over the chicken and toss to coat. Stir in lemon juice, grated Parmesan cheese, parsley, and pepper. Heat on high for 15 to 30 minutes to warm. Place chicken in wraps or on rolls with with lettuce and extra shredded Parmesan cheese on top.