This salad is always a big hit at parties and picnics. It may seem an odd combination of items, but the results are delicious. The salad will keep for 2 days in the refrigerator.
Combine the broccoli, celery, raisins, and sunflower seeds in a large bowl and stir to combine.
Make the dressing by whisking the remaining ingredients in a small bowl until smooth.
Add to the broccoli mixture and toss well. Refrigerate salad at least 2 hours before serving to allow flavors to mellow.