hmm have watched so many video's on how to make butter few did with a stand mixer and several others using small food processors. All of them put the whole milk in, only a couple actually processed the buttermilk out of the butter, but it is a very important step. One lady did ice water baths with paddle on the butter until water ran clear the more buttermilk you get out the longer the butter will last. Haven't tried it yet myself but my stand mixer is ready and waiting.