There are a few different kinds of buttercreams you can choose to make, ranging from easy to insanely complex. If you are short on time, ingredients, or patience, this recipe is the way to go. The beauty of this buttercream recipe is that you really don't have to follow it at all. This is as basic and unsophisticated as buttercream gets, meaning you can go crazy as far as ratios and flavorings according to your personal taste. However, the downside is that it is a pretty fragile buttercream, meaning that if it's too warm, it'll turn into a goopy buttery mess, and if it's too chilled, it'll be a cold block of butter. Time it so that you make it when you need it or, if making in advance, refrigerate and let it come to room temperature about an hour before serving.
This will make about 1 1/2 cups of buttercream, about enough for one layer of a 9 inch cake.
1-2 cups of powdered sugar
12 oz of room temperature unsalted butter
1 Vanilla bean, scraped
2-3 T of heavy cream (or whole milk)
Pinch of kosher or sea salt
Using the paddle attachment of your stand mixer, cream together the butter and 1 cup of powdered sugar. You can choose to sift the sugar beforehand but I've found that if you cream it long and fast enough, it's not really necessary. Taste, and if you decide it needs more sweetness, gradually add more sugar and cream together. Pour in a tablespoon or two of your heavy cream to loosen and lighten it a bit. Once again, how much liquid you add is entirely dependent on personal taste. Finally, add in the vanilla bean and salt and cream until cohesive. It's best to use this buttercream immediately, but if you're making it in advance, refrigerate until needed and then re-cream to refresh.