Start by bringing a large pot of water to a rolling boil over high heat. Add in the tri-colored veggie rotini pasta and cook according to package instructions until al dente, approximately 8 minutes. Once cooked, drain the pasta and rinse it with cold water to stop the cooking process. Set aside in a large mixing bowl.

While the pasta is cooking, prepare the dressing by combining mayonnaise, sugar, and apple cider vinegar in a small bowl. Mix until all ingredients are well incorporated and set aside.

Now it's time to bring all the flavors together! Add shredded carrots, diced red onions, and shredded mild cheddar cheese to the bowl with the cooked pasta. Give it a good toss to combine all the ingredients.

Finally, pour the dressing over the pasta mixture and stir until everything is coated evenly. Cover the bowl and refrigerate for at least one hour before serving to allow the flavors to meld together.