know (one's) beans

(redirected from know their beans)

know (one's) beans

To be knowledgeable about and/or very familiar with something. I had no idea you were such a good piano player—you really know your beans!
See also: bean, know
References in periodicals archive ?
Daouda's products are meant to be certified so wholesalers know their beans do not involve child exploitation.
Our staff will know their beans from their blends and will be expertly trained in the art of hand-made and perfectly-crafted coffee, which I'm confident will delight our new customers.
MICHAEL and Dante may know their beans when it comes to long words and complex theorems, but they'd be outranked by the average 12-year-old when it comes to popular culture.
Vegetable processors that want to know their beans and other vegetables are free of defects and foreign objects have new options to ensure improved quality while at the same time cutting operating costs.