Make sure your cream cheese is at room temperature for easy mixing. For fast heating, remove the cream cheese from the package and cut into large chunks. Microwave in a medium bowl for 15 seconds.
In a medium bowl, whisk together the cream cheese, milk, powdered sugar, and vanilla. If you want the dip thinner, continue adding milk 1/2 Tablespoon at a time until you reach your desired consistency. Microwave again if needed as sometimes cold milk makes the cream cheese chunky again.