Step 1: Season the Chicken

1. Pat the chicken breasts dry with paper towels.
2. In a small bowl, mix together garlic powder, onion powder, Italian seasoning, salt, and black pepper.
3. Rub the seasoning mixture evenly over both sides of the chicken breasts.

Step 2: Prepare the Slow Cooker

1. Place the seasoned chicken breasts in the bottom of the slow cooker.
2. Add the crushed tomatoes, diced tomatoes, chopped onion, garlic, dried basil, oregano, smoked paprika (if using), and red pepper flakes (if using).
3. Pour in the chicken broth and gently stir to combine the ingredients, ensuring the chicken is submerged in the sauce.

Step 3: Cook the Chicken

1. Cover the slow cooker and cook on low heat for 4-6 hours or high heat for 2-3 hours, until the chicken is tender and fully cooked (internal temperature of 165°F/75°C).

Step 4: Add the Cream and Parmesan

1. About 15 minutes before serving, stir in the heavy cream and grated Parmesan cheese.
2. Let the sauce cook on low for an additional 15 minutes to thicken and meld the flavors.

Step 5: Garnish and Serve

1. Remove the chicken breasts from the slow cooker and plate them.
2. Spoon the creamy tomato basil sauce over the chicken.
3. Garnish with fresh basil and extra Parmesan cheese. Serve with your choice of pasta, rice, mashed potatoes, or crusty bread.