Begin by layering the chicken breasts in the bottom of the crockpot, creating an even layer for even cooking.
In a medium bowl, whisk together the cream of mushroom soup, diced tomatoes (including the juice), chicken broth, Italian seasoning, garlic powder, black pepper, and a pinch of salt until well combined and smooth.
Pour the soup mixture over the chicken, ensuring that the breasts are thoroughly coated in the savory sauce.
Secure the crockpot lid and set it to cook on low for 6 hours or on high for 3 hours.
Once the cooking time is finished, carefully remove the chicken breasts from the crockpot and shred them using two forks.
Return the shredded chicken to the pot.
Stir in the broken spaghetti pieces and heavy cream, mixing everything together until the spaghetti is well integrated into the sauce.
Close the lid again and cook on high for an additional 30 to 40 minutes, or until the spaghetti is tender and fully cooked.
Once the spaghetti reaches your desired tenderness, stir in the shredded mozzarella cheese, allowing it to melt into the creamy concoction.
Taste the final mixture and adjust the seasoning, adding more salt or pepper as needed to enhance the flavors.
Notes
Serve with fresh basil and extra cheese for added flavor.