I really like using Spirals for macaroni cheese! They make it right...elbow macaroni or penne will suffice, but it's not the same.
Boil them until only just done in well salted water
Make a thick white sauce and add lots of good tasty grated cheese and a pinch of mustard. Can be a proper white sauce, or milk/cornflour or at a pinch melted philly with some pasta water, but that can be overly sticky-icky
for sauce thickness I tend to go thick enough to gloop, but let it down with some double cream so it will just pour and settle through the pasta shapes
drain the pasta, tip it into a deep dish or roasting dish, and stir through as much grated cheese as you like, even poke in bits of mozzarella if you like it
tip the sauce over the pasta and shoogle it about, don't stir it when the sauce is on it as that makes it claggy.
we like bacon over the top and MORE cheese, then into the oven with it until the cheese and bacon is all toasty and crisp.
Some people just put pasta in cheese sauce and call that Macaroni Cheese, they are very very wrong, that is just cheesy pasta and not nearly as nice. No, it isn't