Commonly used by gumshoes in books by Chandler and Spillane. If something is as good as done or will be done very easily is said to be "duck soup."
It's duck soup from here on out.
Duck Soup is a gathering of sad and single people on a Sunday night making one last ditch effort to 'get lucky' at the weekend. Duck Soup is often frequented by lonely cougars, and fag hags but never a hottie (unless they are there to make sport of all the losers).
This phrase was coined after the 1933 movie of the same title, directed by Leo McCarey, written by Bert Kalmar and Harry Ruby and starring the Marx brothers.
A gathering of Duck Soup is aptly named, because Groucho Marx described Duck Soup... '"Take two turkeys, one goose, four cabbages, but no duck, and mix them together.'
In other words, all the left over or inferior crap thrown in together, but nothing exotic or tasty. thus we are in human terms left with overweight, balding, sweaty men and women, none of whom are attractive, all trying to score each other.
Jeffy; Damn Jo, look at all of these sad lonely people here at the house of Ales, whats going on?
Jo: Its Sunday night Jeffy, they are Duck Soup!
When you are excessively sweaty (preferrably upon finishing at the gym), you take your hand and use it to accumulate the sweat from your testicles and wipe your hand on a friend's face.
Guy 1: "Dude, that was an awesome work out!"
Guy 2: "Man you're so sweaty though"
*Guy 1 performs duck soup*
Guy 1: "What the fuck dude, duck soup is so nasty!"
When a Male is having anal sex with one partner he then ejaculates in the partners anus to then suck his own seamen out with a straw.
So I came in her ass the then I had some duck soup