Bring a large pot of water to a boil over high heat. Add a big pinch of salt and the pasta and cook according to the package directions until the pasta is tender. Drain the pasta, rinse with cold water and set aside.
In a large bowl, mix together the honey mustard dressing, mayonnaise, sour cream and apple cider vinegar. Add the pasta, potatoes, carrots, celery, eggs and bell peppers. Mix until all the ingredients are well coated.
Taste and adjust the seasoning with salt and pepper. Refrigerate until ready to serve. When ready to serve, put into a serving bowl and garnish with the scallions.