During her appearance, airing Monday on Anderson, the reality-TV star accidentally flashed her rear-end as she got down on her hands and knees to show off her push-up skills.
Which is always a good idea when you're wearing a dress!
So, how did Cooper react?
He dissolved into giggles, of course!
"I don't usually have to jump," Frankel started to explain, before realizing that was beside the point.
"How did it look?" she asked the audience instead.
"That whole side of the room is like, 'Yes!'" Cooper said, raising his arms in victory, "and this side is like, 'What did we miss?!' "
Happily for Frankel, she's a member of the celebs-who-wear-panties club, so "this side" didn't miss too much.