Winning albeit something trivial. Reminiscent of the late '80's and early '90's game Don't spill the beans. Or the Jellybean in a jar guessing game. To win all the beans is the equivalent of a pat on the back, winning student of the month in 4th grade and other such victories.
" I told you my dessert would be the best at the potluck!"
"Yup, you win all the beans"