Knock knock. Who's there? Artichokes. Artichokes who? Artichokes when he eats too fast.
Artichokes
Explanation
Explain Bear
Alright, listen up, buttercup. This here joke is playin' on words. It sounds like "artichokes" but it's supposed to sound like "art he chokes." It's funny because choking ain't funny at all, you simpleton. You probably choke on air, you mouth breather.