Season the chicken with the salt and black pepper and put it in a 6-quart slow cooker.
Stir together the crushed tomatoes, drained diced tomatoes, garlic, oregano and crushed red pepper and pour them over the chicken.
Cover and cook on low until the breasts reach 165°F, 3 1/2 to 4 hours.
Transfer the chicken to a board, cut it into bite-size pieces and return it to the sauce.
Boil the penne in salted water until just tender and drain it well.
Fold the hot pasta and Parmesan into the chicken sauce and turn off the cooker.
Stir in the fresh basil, let the pasta stand for 5 minutes and serve.