Make Homemade Blue Cheese Dressing: In medium bowl, whisk together the sour cream, mayonnaise, and buttermilk.

Crumble the blue cheese and stir it into the dressing. Taste the dressing and adjust flavors as needed: adding more blue cheese, salt, and pepper to taste.

Dressing can be made ahead 3 - 4 days but make it at least a few hours. Refrigerate before serving to allow flavors to meld. Top with more blue cheese crumbles before serving.