Prep the broccoli: Blanch the broccoli florets in boiling water for 1-2 minutes. Immediately transfer to an ice bath to stop cooking and keep them crisp.
Combine salad ingredients: In a large bowl, mix the broccoli, red onion, bacon bits, sunflower seeds, raisins, and shredded cheese.
Make the dressing: In a small bowl, whisk together mayonnaise, apple cider vinegar, sugar, salt, and pepper until smooth.
Toss the salad: Pour the dressing over the broccoli mixture and toss gently to coat all ingredients evenly.
Chill: Refrigerate for at least 1 hour before serving to allow flavors to blend.