This is an easy and delicious frosting that complements any cake or cupcake.
Using a stand alone mixer fitted with a paddle attachment, cream the butter over medium speed until light and pale, about 6-7 minutes. With the speed on low, add the kosher salt and gradually add the sugar until incorporated. Add the vanilla paste or extract and heavy whipping cream. Mix on low until they are well blended and scrape down the sides. Increase speed and beat for an additional 5 minutes.
If too thick, add a teaspoon of heavy whipping cream until it reaches desired consistency. If too thin, add ½ cup of powdered sugar at a time.
At this point you can refrigerate (up to 1 week) or freeze (up to three months). Make sure you wrap the frosting tightly and remove any air bubbles. Thaw overnight in the refrigerator the day before using and beat for a few minutes to get the light and fluffy texture.