With a handheld or stand mixer fitted with a paddle attachment, beat the butter on medium speed until creamy, about 2 minutes.
Add 4 and ½ cups confectioners’ sugar, the heavy cream, and vanilla extract.
Beat on low speed for 30 seconds, then increase to medium-high speed and beat for 2 full minutes.
Taste. Add a pinch of salt if frosting is too sweet.
You can control the consistency at this point—add up to ½ cup more confectioners’ sugar if frosting is too thin or more heavy cream if frosting is too thick (add only 1 Tablespoon at a time, beat together, then taste and add more if desired).
Use immediately or cover tightly and store for up to 1 week in the refrigerator or up to 3 months in the freezer.
