In a medium bowl, whisk together the mayonnaise, sour cream, and buttermilk until smooth.
Add the dried dill weed, parsley, chives, onion powder, garlic powder, salt, and pepper. Whisk until well combined.
Stir in the fresh lemon juice. Start with 1 teaspoon and add more to taste, if desired.
Pour the dressing into a jar or airtight container. Chill in the refrigerator for at least 30 minutes before serving to allow the flavors to meld. The dressing will keep in the refrigerator for up to a week.
Notes
This homemade ranch dressing is perfect for salads, as a dip for vegetables, or as a sauce for chicken or fish.