While you're chopping up your broccoli florets, bring a large saucepan of salted water to a boil. Toss the florets into the boiling water and blanch for about 3 minutes, or until they're slightly softened and bright green. Drain and rinse in cold water.
Add broccoli, carrots and onion to a mixing bowl. Mix well.
In a small bowl, combine mayonnaise, sugar and vinegar and mix well. Add to the broccoli mixture and mix well.
Stir in raisins, bacon and sunflower seeds. Serve immediately or store in an airtight container in the refrigerator until ready to eat.
Notes
This is a great dish to bring for a get together. It's hard to resist all the crunch and deliciousness this salad provides!