Butter (1 cup)
in the bowl of a stand mixer fitted with the paddle attachment.
Mix on a high speed until the butter is pale and fluffy, about 5 minutes.
Powdered Confectioners Sugar (2 cups)
Dark Cocoa Powder (1/2 cup)
and mix until it just comes together.
Milk (1/4 cup)
and mix on a high speed until light and fluffy.
Frost your cake and decorate as desired. Serve and enjoy!