Swiss Meringue Buttercream Basics

Swiss Meringue Buttercream Basics

Even starting this blog with the admission that I'm going to be writing about one narrow subject at first, baking technique, is a step of faith. Faith that the E/INFP in me will actually thrive within such external constraints. It's been true in the past. Give me a box to work within and I'll blast upward instead of sprawling sideways in many unproductive directions. Same principle as the cage for a tomato plant. 

I had been resisting for a while. Well, not exactly resisting, but definitely getting distracted. Wanting the site structure to be perfect (not a chance). Waiting for a generous amount of uninterrupted space to devote only to this (also not a chance). I'd given myself an optimistic date of "first post by the end of March" but instead ended up chasing off to Morocco after a different business venture and from there right into the crushing embrace of the spring wedding season. It's now mid-July, and life has just thrown me another curveball, a disappointment that hit right between the eyes, deflating both in its force and its surprise. But it also made me reevaluate my reasons for not starting this project right now, and finding that they'd evaporated while I wasn't looking.  

So buttercream. Let me begin by saying that the stuff piled on top of grocery store cupcakes... it's not buttercream. Before I began baking myself, I didn't realize that "frosting" and "buttercream" could be such vastly different substances. Real buttercream, and Swiss is a good place to start, is akin to being ushered into the temple when you'd been crouched praying in the dust outside the wall. Buttercream is cloud-like and glorious, for the price of just a few extra steps. They are well worth the effort. And here is something I will say loudly and often: use the highest quality ingredients that you can afford - which usually means local and organic, especially for items like eggs. And absolutely no imitation vanilla, not ever. 


I probably should give someone credit for this recipe, but as with many foundational building blocks, there is just a way that it *works*, no matter whose name you might tack onto it. I've now probably made it a hundred times, but I still remember the apprehension of the first, peering at the candy thermometer as I whisked furiously. Maybe I can spare you some of that angst. In my mind, there are two iron rules of baking. First, read the recipe all the way through, slowly. Comprehending an overview of what you're about to do can save you a lot of headache later. And second, prepare all of your ingredients before you start. In French, it's called mise en place. Baking is exacting, and as a naturally haphazard person, I find it so grounding to adopt the practice of doing all of my measuring and weighing in one fell swoop. The rest of the process can then become much more of a fluid dance.

In light of the mise principle, I'm dividing the recipe into two instructional parts. First, getting out and prepping your ingredients, and second, the actual process. 

If you're making a 3-layer 6" or lightly iced 2-layer 8" cake, these proportions will be perfect. Any larger and you'll want to double.  


  • 1/2 cup egg whites - from 4-5 eggs (depending on size)
  • 1 pound (four sticks) of unsalted butter
  • 1 cup of sugar
  • 2 tsp vanilla 


  • Get out your double boiler, or if you don't have one (like me), a stock pot and a steel bowl big enough to sit on top of it without falling in. Fill the pot with about three inches of water and turn it to medium. I have an electric stove, so this works for me, but gas might need to be set lower. You want the water at a simmer, not a rolling boil. Attach - or have at hand - a candy thermometer. Once you've done this many times, you can tell the temperature by eye alone, but at the beginning it's best to be able to confirm with a thermometer that your egg whites are pasteurized. 
  • Separate your eggs. You can use a special tool for this, but I just rock the yolk gently between the two halves of the shell until the white has all fallen into a bowl beneath. You want to make sure that no yolk gets in with the white. This is one of those details that matters. If you accidentally break the yolk, save that egg for another recipe or fry it up and eat it. Another very helpful practice is to separate the whites into a little bowl, then dump each white from that bowl into the measuring cup. That way there's no risk of one broken yolk contaminating all of the whites. 
  • Soften your butter. The very easiest way to do this is to take it out of the fridge the night before. Butter is totally fine at room temp for a day or three, as long as the room doesn't rise above about 78 F. The other way is to unwrap and soften in the microwave on very low power. It should be soft enough to easily poke your finger through the whole stick. Chop each stick into a few large chunks. 


  • Measure out the cup of sugar and the 1/2 cup egg whites into the top bowl/ top of the double boiler and give it a good whisk to mix the two. Don't do this until your water is at a low simmer and your attention is undivided. Whisk every 20-30 seconds or so to keep the mixture moving. If you neglect it, the egg will start to cook and turn into white stringy wisps. Once the mixture  reaches 140 F, either transfer it immediately to the bowl of a standing mixer fitted with the whisk attachment or go at it with a hand mixer in the same bowl - it will still be hot! Mix on medium speed for about 10 minutes or until the contents turn white and start to thicken (see the photo above... the "wide dissolving ribbon" explanation is not as helpful as an illustration). 
  • Add the softened butter a few chunks at a time, mixing well between each one. Toward the end, the buttercream might start to look curdled and chunky. Just keep going. After a few more minutes of whipping, the texture should become smooth and very shiny. 
  • Add in the vanilla, scrape down the sides, and beat until combined. 

Now... here's the part I love most. Once you've mastered a buttercream, you have at your disposal the most beautiful creamy canvas on which to paint other flavors. Of course, you could leave it at vanilla, or amp up the vanilla with a scraping from one vanilla bean. But you could also add dark chocolate or cocoa butter, a splash of salted caramel, or a dollop of mascarpone cheese. Here is where formula ends and creativity can take over. And ultimately that's what baking is. You master the science, and you can move on into the art. 

Intro to Tart Shells | Chocolate Pastry Crust

Intro to Tart Shells | Chocolate Pastry Crust