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

Prepare the Broccoli: Blanch broccoli florets in boiling water for 1 to 2 minutes. Transfer to ice water to halt cooking. Drain and set aside.

Make the Dressing: Combine ranch dressing, mayonnaise, and sour cream in a mixing bowl. Whisk until smooth, adding milk for desired consistency.

Combine the Ingredients: In a large bowl, add cooled pasta, blanched broccoli, peas, and bacon bits. Gently fold to distribute ingredients evenly.

Incorporate the Dressing: Pour dressing over pasta salad and fold gently until everything is coated.

Chill the Salad: Cover with plastic wrap and refrigerate for at least 2 hours to allow flavors to meld.