once upon a chef
– 1 pound macaroni, cavatappi, farfalle, or fusilli pasta – 1 cup mayonnaise, best quality such as Hellmann's or Duke's – 1 cup sour cream – 3½ tablespoons sugar – 1 tablespoon Dijon mustard – ¼ cup apple cider vinegar – ¼ cup water – 1¼ teaspoons salt, plus more for cooking the pasta – 1 teaspoon freshly ground black pepper – ¾ teaspoon onion powder – ½ cup finely diced or grated carrots, from 1 to 2 carrots – ¾ cup finely diced celery, from 2 to 3 celery stalks – 1 red, yellow, or orange bell pepper, finely diced – 6 scallions, light and dark green parts, finely sliced – ¼ cup finely chopped fresh basil
Bring a large pot of salted water to a boil. Cook the pasta until tender according to package instructions (about 1 minute past al dente).
Drain the pasta in a colander and let cool to room temperature.