For an easy homemade Ranch Dressing: Whisk 1/2 cup Hellmann's Mayonnaise, 1/4 cup sour cream, 3/4 cup buttermilk, 1 tsp chives, 1/2 tsp parsley, 1/2 tsp dill, 1/2 tsp garlic powder, 1/2 tsp onion powder, 1/2 tsp salt, and 1/4 tsp pepper together in a large bowl until well-combined. Cover and refrigerate for at least 30 minutes before serving.