Many recipes call for softened, or room temperature, butter. The easiest way to bring butter to room temperature is to let it sit at room temperature for about a half-hour to an hour, but I usually quick-soften my butter by cutting it into cubes, then letting it sit out for about 15-30 minutes.
Softened butter should look like the photo here – you should be able to indent it with your finger, but not press all the way through. Think of the consistency of ice cream, rather than the consistency of whipped cream, when judging whether your butter is soft enough, but not too soft.
In many cases, butter must be softened so that it can blend more easily with certain ingredients, like sugar, for example. In other cases, your butter will need to remain cold – like if you’re working with pastry dough – so be sure to check your recipe before you start. If you’re incredibly short of time, cut your butter into very small cubes, then place it in your mixing bowl. Beat it on high speed for about 3-4 minutes, scraping the bowl every minute or so, to soften it.