Eating mac and cheese at the barn - and somebody asked me if horses like it.
The answer is...not so much on the cheese. Dairy products aren't very good for horses - their system isn't meant to take any animal proteins other than milk, and that before weaning, for all that some racing people used to swear by eggs as an equine "pick me up."
The mac part, though? Sure...but they'd prefer it uncooked. Horses love uncooked pasta and it's a great treat for them. In moderation, of course.