I heard a different version of this joke:
A non-Jew walks into a Jewish restaurant. He says to the waiter, "You know, I've never really had Jewish food before. What do you recommend?"
The waiter thinks for a moment and then says, "You should try the matzoh ball soup. Everybody loves it."
The man says, "Ok, bring me a bowl".
So, the waiter brings the man a bowl of matzo ball soup. The man tries it, he loves it, he eats the whole thing. He says to the waiter, "Wow, that was great! Bring me another bowl!"
The waiter brings the man another bowl of soup. Again, the man loves it and eats the whole thing. He asks for a third bowl.
The waiter brings him a third bowl and the man begins to eat.
As the waiter turns to leave, the man stops him and says, "You know, this is really good. Thank you for the recommendation. I just have one question:
What do they do with the rest of the matzo?"
I feel entitled to tell this terrible joke because I spent yesterday making and then serving about 100 matzo balls. Happy Passover, everyone.
Editor's note: the "What do they do with the rest of the matzo?" line is oft attributed to Marilyn Monroe.