Spray slow cooker insert with cooking spray.
Place halved potatoes in slow cooker.
In a medium bowl, whisk together olive oil, Italian seasoning, minced garlic, Parmesan, salt, and pepper.
Pour mixture over potatoes and toss well to coat evenly.
Cover and cook on LOW for 4-5 hours or HIGH for 2-3 hours until tender.
Stir occasionally if possible for even cooking.
Check tenderness with fork at minimum cooking time.
When done, stir in half the fresh parsley.
Transfer to serving bowl, top with remaining parsley and extra Parmesan.
Season with additional salt and pepper if needed.