Pour cream and salt into bowl of stand mixer and mix on high. In essence, you'll be making whipped cream...only you're going to whip the cream beyond this point. About 3 minutes.

Keep beating a few more seconds. You'll notice water start to separate from the butter. This is actually buttermilk and can be saved for future use.

Once buttermilk forms, remove bowl from stand mixer and fill bowl with cold, running water. With your hands, squeeze the butter together to form a ball. Keep massaging the ball of butter under cold water until the water runs clear. This will assure that all the buttermilk is removed and that your butter will stay fresh longer.

Once water runs clear, remove ball-o-butter from bowl and wrap in parchment paper and chill in refrigerator, or slather on some toasted bread like I did!