Mise en place - If using fresh herbs, mince the parsley and chives, enough to yield 1 tablespoon each.
Combine - Whisk together ½ cup mayo, ½ cup sour cream, and ½ cup buttermilk until smooth. Add 1 teaspoon dill, the minced/dried parsley and chives, ¼ teaspoon onion powder, ½ teaspoon garlic powder, ¼ teaspoon salt, and ⅛ teaspoon pepper. Whisk until combined. Add the lemon juice, and whisk again.
Chill - Pour into a jar and chill in the refrigerator until ready to serve, giving the flavors time to meld.