Place 1.5 lbs of halved baby potatoes at the bottom of the slow cooker.
Place 1.5 lbs of boneless skinless chicken breasts directly on top of the potatoes.
In a small bowl, whisk together 2 tbsp melted butter, 1 tbsp minced garlic, 1 tbsp Italian seasoning, 1 tsp salt, 1/2 tsp black pepper, 1/4 cup chicken broth, and 1/2 cup heavy cream.
Evenly pour the liquid mixture over the chicken and potatoes.
Cover and cook on LOW for 6-7 hours or HIGH for 3-4 hours, until the chicken is thoroughly cooked (internal temp of 165°F) and potatoes are fork-tender.
Sprinkle 1/2 cup grated Parmesan cheese evenly over the top during the last 15 minutes of cooking, allowing it to melt into the creamy sauce.
Top with 2 tbsp chopped fresh parsley right before serving.