Julia Louis-Dreyfus is responsible for some of the funniest moments on TV thanks to her roles in Veep, The New Adventures of Old Christine and Seinfeld. And while those shows were all tightly scripted, Louis-Dreyfus says that there were some moments when she was allowed to improvise, and they definitely paid off.

Speaking to USA Today, Louis-Dreyfus reveals that one of the most memorable lines to come out of Seinfeld was all thanks to her quick thinking. It happened during the show’s fourth season episode “The Pick,” during which Elaine learns that her Christmas card photo, which was taken by Kramer (Michael Richards), revealed her nipple.

After complaining to Jerry and George (Jason Alexander) that she’s the subject of ridicule in her office —”Everybody’s calling me ‘nip’!”— George whines, “How come I didn’t get a Christmas card? Everybody else got one. Jerry got one. Kramer got one. I thought we were good friends. I don’t get a Christmas card? I don’t get it.”

Louis-Dreyfus, who is as skilled with physical comedy as she is with incredible line-delivery, recalls that her response to George was something she worked out on her own.

“In rehearsal, I came up with the idea of grabbing his head and shoving it between my breasts back and forth, saying: ‘You want a Christmas card? Here’s your Christmas card!’ That made it into the show, and I think it helped the scene.”

Considering how iconic that line has become, “I think it helped the scene” is a pretty modest view of things. (You know what’s not modest? Elaine’s raunchy Christmas card.)

Louis-Dreyfus is currently starring in Nicole Holofcener’s You Hurt My Feelings, which is in theaters now.