Beat butter in bowl of a stand mixer or electric hand mixer, on medium speed until smooth, fluffy, and turns lighter in colour.

Scrape down sides of bowl. Add in confectioners sugar, cream, and vanilla.

Mix on low until all powdered sugar is incorporated, then mix on high for about 2 minutes until fluffy.

You'll want a stiffer consistency. If it's too stiff, add more cream. If it's too thin, add more sugar.