Gather your ingredients together.
Cook bacon in a skillet over medium-low heat, until crisp, 5–7 minutes; transfer to a paper towel–lined plate.
When cool chop into pieces.
Whisk shallots, sour cream, buttermilk, chives, and white wine vinegar in a small bowl; fold in blue cheese.
Season dressing generously with kosher salt, freshly ground black pepper, and more vinegar, if needed.
Cut 1 small head of iceberg lettuce into 4 wedges; place on plates and spoon dressing over.
Top with bacon, red onion, tomatoes, avocado, more crumbled blue cheese and chopped chives.
This is a wonderfully delicious salad. Enjoy!