Start by preparing your creamy dressing. In a medium-sized bowl, whisk together the mayonnaise, honey, vinegar, grated shallot, and milk. Whisk until smooth and fully blended. Once combined, cover the bowl and place it in the fridge. This allows the flavors to meld while you prep the rest.
Bring a large pot of salted water to a boil. Add the elbow pasta and cook according to the package directions until al dente. Avoid overcooking, as soft pasta won’t hold up well in the salad. Drain the pasta in a colander and rinse it under cold water to stop the cooking process and cool it down quickly.
Transfer the cooled pasta to a large mixing bowl. Pour in the chilled dressing and stir until the pasta is well coated. Add in the diced carrots and celery, mixing them in evenly. The crunch from the veggies pairs beautifully with the creamy pasta and adds freshness.
Once everything is mixed together, cover the bowl with plastic wrap or a lid. Refrigerate the mac salad for at least 1 hour or overnight for best results. Right before serving, sprinkle chopped green onions over the top for a fresh pop of flavor and a little extra color.