the appearance of your anal sphincter when you are pushing out or bending over and spreading your cheeks
that chick i hooked up with was so naughty that before she sat on my face she made sure I got a good hard look at her upside-down crumbcake when she straddled my face.
First used in a smosh video (Trivial Pursuit: Try not to laugh #6 (Chosen Edition))
It’s when you crumble up a bunch of cookies and sprinkle it over someone’s face
Spencer: which country is home of the cookie-like Crumbkakke
Shayne: I’d never partake in that! You know that! I’d never fap! I do not watch crumbkakke.