Step 1: Season and Set the Chicken Base - Place the chicken breasts into the slow cooker in a single layer. Sprinkle the salt, black pepper, and garlic powder evenly over the top. Give it a quick rub with your hands if you want to make sure the seasoning sticks.
Step 2: Add the Cabbage Layer for Texture - Add the chopped cabbage right on top of the chicken. Do not worry if it looks like a lot at first. It will cook down quite a bit as it softens.
Step 3: Pour in the Creamy Alfredo Mixture - Pour in the chicken broth, heavy cream, and Alfredo sauce. Try to spread it evenly so everything gets coated. You do not need to stir at this stage.
Step 4: Slow Cook Until Tender and Flavorful - Cover the slow cooker with the lid and cook on low for four to five hours. This is where the magic happens. The chicken becomes tender and the cabbage soaks up all that creamy flavor.
Step 5: Shred and Bring Everything Together - Once the cooking time is up, use two forks to shred the chicken right in the slow cooker. It should pull apart easily. Stir everything together so the chicken, cabbage, and sauce are well combined.
Step 6: Finish with Parmesan for a Creamy Finish - Add the shredded Parmesan cheese and stir until it melts into the sauce. Let the dish sit for about five to ten minutes before serving so the sauce can thicken slightly.