In a bowl, whisk together buttermilk and mayonnaise until smooth. Add parsley, dill, chives, garlic powder, onion powder, and half the salt and pepper. Whisk until blended. Taste and add more salt and pepper as desired.
Notes
Store in an airtight container in the refrigerator for 3-4 days.
To make with dried herbs, use ? less amount. 1 tablespoon fresh herbs equals 1 teaspoon dried herbs.