Add tomatoes, pasta sauce, garlic, salt, Italian seasoning, basil and pepper to a 3-6 quart slow cooker. Stir.
Whisk together cream and corn starch and add to the slow cooker.
Add chicken breasts and press down into the sauce.
Cook on low for 3-5 hours, until a meat thermometer reads 165 degrees F. The exact cook time will depend on your slow cooker -- a fuller slow cooker will take longer to cook, so a larger one will cook faster.
Stir in fresh basil and serve over pasta, rice, or with a salad and veggies!