Place the blue cheese and buttermilk in a medium-sized bowl and mash the blue cheese with a fork until the desired degree of chunkiness is reached. Add the remaining ingredients and stir until combined. Cover and chill for at least 3-4 hours before serving to allow adequate time for the flavors to develop (for best results chill overnight). Taste and add more salt and pepper if desired. Keep stored in an airtight container in the fridge where it will keep for up to a week.Makes about 1 1/2 cups.
Notes
For a low calorie blue cheese dressing use low fat mayonnaise and sour cream.