Mix all (except dijon mustard, flour and bread crumbs) into a baking dish and bake covered at 350F for 30 minutes. (Yes, the macaroni is uncooked and the cream cheese is solid, at this point!).

Remove and stir. Add flour & dijon and mix well. Let it sit covered until ready for dinner. Top with bread crumbs. Bake again at 375F for another 30 minutes uncovered.

Remove and let sit 5 minutes before serving.

Optional: Add cooked ham or bacon 1/2 way through and stir in.