Place the cream cheese in a mixing bowl fitted with a paddle attachment, and mix on low speed until smooth and creamy.
Cream the butter and icing sugar in another mixing bowl until pale and fluffy.
Slowly add the cream cheese to the butter mixture and mix at medium-high speed until the frosting is combined.
Add the dulce de leche and mix until well incorporated and smooth.
Your frosting will be soft at this point. Chill in the refrigerator until set.