Lightly coat the inside of a slow cooker with nonstick spray. Place potatoes into the slow cooker. Stir in olive oil, butter, garlic, oregano, basil and dill, and gently toss to combine; season with salt and pepper, to taste.
Cover and cook on low heat for 4-5 hours or high heat for 2-3 hours, or until tender.*
Serve immediately, sprinkled with Parmesan and garnished with parsley, if desired.
