Whisk in oil, vinegar, white onion, 1 tablespoon green onion, mustard, parsley, honey and lemon peel in a large bowl until blended. Season with salt and pepper.
Add potatoes to dressing and combine gently. Season to taste. Cool.
To serve, place lettuce around edge of platter, place potato salad in the center and sprinkle over with bacon, blue cheese, egg and remaining green onion.