Using either the paddle attachment of a stand mixer or a hand mixer, whip the butter pieces for 5-7 minutes, occasionally scraping down the bowl.
On low speed, add in 2 cups of the powdered sugar, mixing until completely incorporated into the butter.
Add in 2 tsp of vanilla extract and mix to combine. Beat for about 60 seconds.
Add in an additional 2 cups of powdered sugar and beat on low speed until the powdered sugar is completely mixed in.
Increase the speed to medium-high and beat for 3 minutes.
Add in last cup of powdered sugar along with 2 tablespoons of heavy whipping cream and ½ tsp of vanilla extract.
Beat on low speed until the ingredients begin to mix together, then increase speed to medium-high and beat for another 4-5 minutes.
Scoop the frosting into a piping bag fitted with a star tip and set it to the side.