Beat the softened butter on medium speed until creamy and pale, about 2 minutes.

Add half the powdered sugar and mix on low until mostly combined, then beat on medium until smooth.

Add the remaining powdered sugar, vanilla, salt, and 2 tablespoons of milk or cream.

Beat on high speed for 3–4 minutes until light and fluffy.

If it’s too thick, add a little more milk, one teaspoon at a time, until it reaches your desired consistency.

Use right away or store in an airtight container in the fridge for up to a week—just bring it back to room temp and rewhip before using.