I'm not sure which episode it is, except that it's shortly after Rebecca joined the show.
Jesse is watching Rebecca on her talk show. He tells Joey that he asked her out on a date and she's supposed to answer him by winking. He says "Once for yes, twice for no". Joey says that if she gets something in her eye, they'll be engaged. Rebecca winks twice and Jesse's happy because their date is on.
He should have said "Once for no, twice for yes".