When a woman with a flabby ass presses it into your face. This could be done to anally motorboat, perform analingus or cunnilingus. Can be used in both a positive and negative sense.
"How did things with that girl go last night?"
1) "They went well until she gave me the ass potato pancake"
2) "It was pretty dull until she gave me the ass potato pancake...then it was awesome!"