Red's Beauty Tip #48

I can't remember the episode this was shown at the end of and I can't find a video of it anywhere, but The Red Guy says:

"Red's Beauty Tip #48: People pass me by on the street and go: 'HEY RED, how come you're so dashing?'
Well I'm slim hipped and all muscle, also having an outy belly button don't hurt neither! END OF BEAUTY TIP"

It's so funny, it's the funniest sketch of the whole show, I want to know what episode this was shown on.