3/4 cup mayonnaise
1/2 cup buttermilk
1 tablespoon minced parsley
2 teaspoons minced onion
1 to 2 garlic cloves, minced
1/2 teaspoon coarsely-ground black pepper
1/4 teaspoon salt
Splash of white vinegar, optional

Combine all ingredients in a large lidded jar and shake them well. Chill at least 30 minutes. The dressing keeps in the refrigerator for at least 5 days.

Jalape? Ranch Dressing
Add one or two minced fresh or pickled jalape? pods, from which the seeds and stem have been removed.