Cream the butter in a stand mixer until it is really light and fluffy, at least 3 minutes.
Gradually start to add the sugar as the mixer is running, about 1/2 cup at a time.
Add the vanilla extract.
Add 2 tablespoons of heavy cream and beat the frosting for 2 to 3 minutes. If the frosting is too thick, add a little more cream until you get the consistency that you like.