Beat butter with an electric mixer on medium speed until creamy.
Sprinkle salt over butter and stir again to combine.
Gradually add powdered sugar ½ cup at a time, making sure each cup is completely mixed in before adding more.
Turn down mixer to low speed and add the heavy cream one tablespoon at a time.
Once ingredients are incorporated, gradually increase speed to high and beat for 30 seconds.
Add vanilla and stir well.
Adjust to consistency if needed, if too thick add a little more cream, if too thin add more sugar, if too sweet, add a pinch of salt.
Chef's notes: This frosting will be fine at room temperature for 2 days or in the refrigerator in an airtight container for 1 week.