Beat butter with a mixer (I use my KitchenAid with the paddle attachment). Gradually work in the sugar, alternating with the cream and beating well after each addition. If the frosting is too thick to spread, add a little more cream, a teaspoon at a time. If it is too thin (which is unlikely), refrigerate for a few minutes; it will thicken as butter hardens. You can add up to 2 teaspoons of vanilla, but if you need white frosting leave the vanilla out!
Recipe by This Week for Dinner at https://thisweekfordinner.com/an-amateurs-guide-to-making-super-cute-cakes/