These are truly the easiest meatball subs! We took a bunch of shortcuts by making everything store-bought and these are a winner! All you do is let frozen meatballs cook in a crockpot with sauce and then layer up your subs. It's the perfect dinner for a busy day and you really can't mess it up. We got mostly everything from Costco to make it a Costco dinner, but you could easily substitute with whatever works for you!