For the frosting: add sugar, cream cheese, milk, and vanilla to a large bowl. Use a hand mixer on medium speed to mix until smooth and creamy, scraping the sides as needed. Continue mixing until frosting reaches a fluffy and creamy consistency.
Frost each shortcake by spooning the frosting and then cover with the berries.
The leftover berries can be placed on the plate next to each shortcake.
Notes
The vanilla dessert shells can be found in the bakery section or near the strawberries.
Can use heavy cream in place of the milk, if you would like fluffier frosting.