Bring a large pot of water to a rolling boil over high heat. Add the rotini pasta and cook for 8–10 minutes until al dente; drain and rinse under cold water.

Chop the broccoli into small, bite-sized pieces and finely dice the red onion.

In a medium bowl, combine mayonnaise, sugar, white vinegar, salt, and pepper. Whisk until smooth.

In a large bowl, add the cooled rotini pasta and pour in the dressing. Toss until well coated.

Fold in chopped broccoli, bacon, cheddar cheese, onion, cranberries, and walnuts carefully to combine.

Cover and refrigerate for at least 1 hour before serving to allow flavors to meld.