Beat the butter first: In a large bowl, beat the softened butter on medium speed until smooth and creamy (about 1-2 minutes)
Add cream cheese: Add the cold cream cheese (cut into a few chunks) and beat on medium speed until well incorporated and smooth, about another 1-2 minutes (TIP: Don’t overbeat once the cream cheese is added — just beat until combined so it stays firm!)
Add sugar and flavoring: Add 2 ½ cups powdered sugar, vanilla extract and salt. Beat on low speed at first (to avoid sugar clouds), then increase to medium-high and beat until the frosting is thick, smooth and fluffy (about 2 minutes)
Adjust as needed: If it’s too soft for piping or you want it stiffer, beat in the remaining ½ cup of powdered sugar a little at a time until you get the right consistency
