Beat butter and sugar on low, then increase the speed to medium and beat for 3 minutes, stopping once to scrape the sides.
Add the desired flavoring along with the whipping cream and beat on high for 2 minutes, scraping halfway and continuing for the additional minute.
Pipe onto cupcakes using decorator tip 1M or spread. This frosted 21 cupcakes as shown in the picture above. For a layer cake you may want double the recipe or at least use 1-1/2 times the original ingredients.