Cook bacon: Preheat oven to 400°F. Line a large rimmed baking sheet with aluminum foil. Lay bacon strips on prepared baking sheet. Bake 20-25 minutes or until crispy.
Crumble bacon: Remove cooked bacon from baking sheet and drain on paper towels. Crumble and refrigerate until ready to use.
Make dressing: In a large bowl, whisk together mayonnaise, vinegar, sugar, mustard, salt, and pepper.
Add broccoli and other ingredients to dressing: Add broccoli, onion, cheese, cranberries, and raisins to dressing. Toss to coat.
Add toppings: Salad can be served immediately, but for best results, chill for at least 2 hours before serving. Just before serving, sprinkle with sunflower kernels and cooked bacon.
