Cook the Pasta: Bring a large pot of salted water to boil. Add the rotini or penne pasta and cook according to package instructions until al dente, typically 8-10 minutes. Drain and rinse under cold water to cool.

Prepare the Broccoli: Wash and chop the fresh broccoli into florets. Blanch in boiling water for 2-3 minutes, then transfer to ice water to maintain color and crunch.

Make the Dressing: In a large mixing bowl, combine mayonnaise, red wine vinegar, sugar, salt, and pepper. Whisk until creamy and well-blended.

Combine Ingredients: In a big serving bowl, add cooled pasta and blanched broccoli. Stir in chopped onion and pour in the dressing. Toss gently to coat.

Chill for Flavor Development: Cover and refrigerate for at least 3 hours for flavors to meld.

Add the Bacon Before Serving: Stir in crumbled bacon just before serving for crunch. Serve cold.