Cook the bacon. Cook the bacon in a pan over medium-low heat until it’s crispy, flipping it occasionally. Then, move the bacon to a plate with paper towels to soak the extra grease. After the bacon cools down, break it into tiny bits and keep it in the fridge until needed.
Prepare the dressing. In a large mixing bowl (which can also serve as your serving bowl), whisk together the mayonnaise, granulated sugar, and apple cider vinegar until the mixture is smooth and well combined.
Combine the salad ingredients. Add the broccoli florets, cauliflower florets, diced red onion, and raisins to the bowl with the dressing. Stir thoroughly to make sure all ingredients are evenly coated with the dressing. Then, cover the bowl with plastic wrap or a lid and refrigerate for at least 2 hours, allowing the flavors to meld. The salad can be chilled for up to 6 hours if needed.
Finish and serve. Before serving, remove the salad from the refrigerator and stir in the crumbled bacon and shredded sharp cheddar cheese. Mix well, then serve immediately.