Boil water, add pasta and if using the Trader Joe's fusilli, cook for approximately 7 minutes. Drain, add chopped veggie* of your choice and set aside. (This step can be done early, or while doing the next step).

In a medium sauce pan, heat the butternut squash soup over low to medium heat. While the soup heats, make a roux with the butter and flour (heat butter in a small pan over low to medium heat and blend with flour until consistency is paste like.) Spoon about 1/2 cup of the heated soup into the pan with the roux and combine until mixture is smooth (will be very thick). Add this back into medium pan with remaining soup and stir. This is to thicken the soup up to mimic a cream sauce. Once roux is fully mixed in, added shredded cheese, cayenne and garlic, and stir until the cheese is completely melted. 

Add "cheese" sauce to the pasta and veggies. Stir making sure everything is coated evenly and top with salt and pepper to taste. 

*When I know I want to make this dish, I just double whatever vegetables I am making for dinner the night before and save some for the mac and cheese. But if you don't plan ahead you can just use steamed vegetables, frozen, sauteed, anything!