https://www.cnet.com/news/fresh-cold-brew-in-five-minutes-meet-the-dash-rapid-cold-brew-system/

The traditional method for cold brew is dead simple. Just drop coarsely ground coffee into a container of lukewarm or cold water. Then you mix the ingredients, let steep overnight and drain. The liquid you ultimately separate from your solid grounds is what's commonly referred to as cold brew.   

This method substitutes the heat of standard hot water brewing with lots more time. Proper cold brew also calls for amped-up amounts of coffee. Conventional cold brew recipes call for triple or quadruple the ratio of grounds to water usually used for ordinary drip. That's why a machine billed to whip up cold brew in mere minutes struck me as preposterous. And that's why I had to put the Dash Rapid Cold Brew System to the test.