Costco just started selling a 27-POUND BUCKET of mac and cheese. That's six gallons. It's got 180 servings . . . and it has a shelf life of 20 years.
If you want one, it costs $90 . . . so just $2 per serving. Or maybe it's $90 per serving, if you approach this bucket like I'm going to. Unfortunately, the last we checked, it was sold out online.