Add the ingredients to a large bowl.
Starting on low speed, beat with a handheld electric mixer until light, fluffy, and lump-free. Add the powdered sugar for additional sweetness and stiffness, if desired.
Spread onto a cake or cupcakes, or transfer to a plastic storage bag to use as a piping bag. (Seal the bag, trim one bottom corner, and press the frosting out like a piping bag.)
