LIGHT AND CREAMY FROSTING

3 sticks unsalted butter, cut into chunks and softened
3 Tbsps heavy cream (I used 1% milk and it worked fine)
2 1/2 tsps vanilla
1/4 tsp salt
3 cups confectioners sugar

Beat the butter, cream, vanilla and salt with an electric mixer on medium-high speed until smooth, 1 - 2 minutes.  Stop the mixer and add the confectioners sugar.  Beat on low speed until combined then whip at high speed until light and fluffy, 5 - 10 minutes.

CHOCOLATE VERSION:

Reduce confectioners sugar to 2 and 3/4 cups.  Add 6 Tbsps unsweetened cocoa powder with the confectioners sugar.

When making a smaller batch these are the amounts I used:

1 stick (1/2 cup) unsalted butter, softened in the microwave until just starting to melt
1 Tbsp 1% milk
3/4 tsp vanilla
a pinch of salt
3/4 cup + 2 Tbsps confectioners sugar
2 Tbsps unsweetened cocoa powder
The small batch frosted 12 cupcakes with some frosting left over.