If you're looking for a buttercream recipe that is practically perfect in every way, this is it! You really can't go wrong with Rose's recipe. I mean, she did write the cake Bible, after all. No, literally. Her cookbook is called "The Cake Bible," and it really deserves that title. It's exhaustive, it's exact, and every single recipe has been tested and perfected to the nth degree. It's my go-to guide for frostings, fillings, and yes, even cake (though I adapt the recipes to be gluten free, with varying levels of success!)
This is the frosting I used for James' first and second birthday cakes, and I also used it on the 4th of July to frost some chocolate cupcakes (which explains the festive sprinkles! Also, the terrible icing jobs. I am no professional cake decorator. Sorry internet. I can't be good at everything.) It's a great base recipe for lots of other flavors and colors, and it holds up very well to mix-ins and flavorings. For James' last birthday we did it in lemon, but you can also mix just about any jam, liquor, chocolate, extract, or candy into, and it will work beautifully.
This recipe is technically what Rose calls "neoclassic" butter cream. She call it this because to her, "classic" buttercream involves a candy thermometer and the softball stage of candymaking, and that gets complicated and is prone to disaster. Her "neoclassic" buttercream side steps this terrifying procedure by the addition of corn syrup. Now before you snatch your petticoats up in horror over the addition of corn syrup, hear me out: Frosting is not health food people. It really has no place in a sensible nutritious diet. And is shouldn't, because that's not the point of frosting. The point of frosting is to be sinfully delicious and have no nutritional value whatsoever. So what if it has a little corn syrup in it? It frosting! It's not supposed to be good for you. So please, have a cupcake. With some frosting! It's your birthday ;)
Rose Levy Beranbaum's Neoclassic Buttercream
adapted from The Cake Bible
Makes 4 cups
The reason this is Rose' favorite buttercream recipe (and mine too!) is that the corn syrup acts as a stabilizer to the sugar, and when the sugar and corn syrup come to a boil, it is exactly the right temperature, no thermometer needed. Further, the corn syrup prevents crystallization, so your frosting says practically perfect in every way.
6 large egg yolks
3/4 cup sugar
1/2 cup liquid corn syrup
2 cups (4 sticks) unsalted butter, room temperature
vanilla or other flavoring
Transfer to a storage container, or frost your cupcakes! Enjoy!