Now for a long time I've thought the hardest, grossest thing to clean out of the food processor was the cranberry nut mix for the cranberry relish Mark makes every holiday. That is mostly because the tiny, chunky bits get everywhere, glom up the sponge and generally make a huge mess given only one appliance was used in the making of this holiday favorite.
Today, I am a convert.
Today I have learned that true nastiness likes in the cleaning up of steak tartar. Mostly because each time you find one of those little tiny places you didn't quite get the first time you realize "EWWW!!! DAY OLD RAW STEAK!!!"