Dishes

Alright, listen up, buttercup. This joke is like when you try to be all fancy with a punchline, but it ends up flatter than a pancake. "Dishes" sounds like "This is." So the joke is supposed to be "This is a very bad joke!" But guess what? It's so obvious it's actually cringe. And for the record, most people on the internet think that knock-knock jokes are lame. Just sayin'.