1 stick butter, softened
4 tablespoons milk (or use whipping cream to make it extra creamy)
1 teaspoon vanilla
4 cups powdered sugar (more or less)
In a bowl, beat the butter, milk and vanilla until smooth. Add sugar about 1/2 cup at a time. Make sure the mixer is on low when you add it or you'll get a cloud of powdered sugar. Experience speaking here. Keep beating until it's all smooth. You may need a bit more or less sugar depending on how you like your icing. I am not picky about it so for me, it's easier to just add the 4 cups and be done with it.