In a medium bowl, whisk together the mayonnaise, sour cream, and buttermilk until smooth.
Stir in the dried parsley, dill, chives, garlic powder, onion powder, salt, and black pepper.
Add the lemon juice or vinegar and whisk again. If you prefer a thinner consistency, add a bit more buttermilk, 1 tbsp at a time.
For the best flavor, cover and refrigerate the ranch for at least 15-20 minutes to let the flavors meld together.
Serve cold or store in an airtight container in the refrigerator for up to 1 week.