Food Jokes
Question & answer
Why don't eggs tell jokes?
They'd crack each other up.
Behind the Groan
Laughter with Fragile Shells
“Crack someone up” means make that person laugh hard, while eggs literally crack when their shells break. The answer imagines both outcomes happening at once. Keep the setup brief and serious, then give the familiar phrase without adding an egg accent or extra pun. The double meaning is enough.