In a medium bowl or stand mixer bowl, cream the butter until creaming or about 30 seconds. Always use paddle attachment for cream and not the whisk.

At a low speed add the powdered sugar one cup at a time until all is added to the creamed butter. After all the sugar is mixed increase the speed of the mixer to a medium speed and mix for about 2 minutes, until the frosting is smooth and creamy.

Scrape the sides of bowl, add the vanilla extract, milk, salt, and beat for additional 4 minutes or until light and creamy. Before using the frosting, use a rubber spatula to stir the mixture to get rid of any air bubble and get a creamy buttercream.

Keep the buttercream covered with a damp cloth until ready to use.