I saw this in a recipe book–the idea of putting mac ‘n cheese on a sandwich–and I wanted to try it. I made boxed macaroni and cheese and spread it out on a pan to cool. Meanwhile, I cooked up some onions until they were pretty much dead and some bacon until it was sufficiently crispy.
To build my sandwiches, I buttered some bread and then put the buttered sides together. Then I layered on some spread (mustard and mayo), sliced cheese, onions, bacon, and the macaroni and cheese. I grilled the sandwiches on the waffle iron, buttered sides out. If I would have remembered, I would have added tomato and avocado, but I forgot and put them on the side instead.
They were delicious. And surprisingly filling–I couldn’t eat an entire sandwich.