Iced coffee aficionados argue that the best cup is a cold-brewed cup, so here's a mapped guide to Boston's cold-brew coffee hotspots to see you through to the end of summer. Cold-brewing often produces a less bitter coffee, allowing more subtle flavors to shine through. There are a variety of ways to cold-brew, mostly consisting of a 12-to-24 hour steeping period, either refrigerated or at room temperature, followed by filtering and diluting with cold water. Boston coffee shops have taken note of the trend, and so an increasing number have begun to offer cold-brew coffee in recent years. From dwelltime in Inman Square to Channel Cafe in Fort Point, here’s where to try cold-brew coffee around Boston.