In a large bowl, beat the softened cream cheese and butter together until smooth and creamy.

Add the lemon zest, lemon juice, vanilla extract, and salt; mix until well combined.

Gradually add the powdered sugar, one cup at a time, beating on low speed until incorporated.

Increase the speed to medium-high and whip for 2 minutes until light and fluffy.

Use immediately or refrigerate in an airtight container for up to 5 days.