How to Make the Perfect Swiss Meringue Buttercream
This is my absolute favorite buttercream. I use it for everything from cakes to filling for macarons. Below is the recipe my Easy 1,2,3 Swiss Meringue Buttercream; for more info about buttercreams in general, read on after the jump:
SAMANTHA MAYFAIR CAKES EASY 1,2,3 SWISS MERINGUE BUTTERCREAM RECIPE:
1) Egg whites: 300 grams. This is roughly 6 large egg whites.
2) Sugar: 600 grams. Notice how it is double the amount of egg whites.
3) Unsalted butter: 900 grams. This is two full pounds of butter.
4) 1/4 teaspoon of fine sea salt
Combine the egg whites and sugar in the bowl of stand mixer and set over a double boiler. Cook, stirring occasionally to 175 degrees F.
Place the bowl into the stand mixer and whisk on high until that meringue is stiff, glossy and the bowl is cool. Pro tip: Make sure the bowl is cool otherwise your butter is going to melt and you'll just have Swiss meringue soup instead. And then you'll be sad.
Once the bowl is cool, your meringue (which you can use for any meringue need at this point) should be light as a feather and stiff as a board; it should have balled up around the whisk.
Begin adding your butter in small chunks, waiting for it to incorporate before adding more. Once all the butter is added, the mixture should hold its shape--it will look like frosting!
Add 1/4 tsp salt and give the buttercream one final mix on high speed to incorporate, and add your choice of flavoring.
Some pastry chef pro tips:
A good recipe is all about ratios and the beauty of this recipe is that you can always make this buttercream by simply making your egg whites the base of your ratio, 1, and multiplying that number by 2 to get your sugar and 3 to get your butter.
You can use a 4.5/5 QT stand mixer with this recipe for up to 2 lbs. (908 grams) of butter. Larger volumes than that will require a bigger mixer. You can also use a hand mixer.
Before you get started, make sure that your whisk and the bowl are extremely clean. Any dirt or fat residue left behind will guarantee your meringue doesn't reach its full potential. I wipe down all my equipment with a clean towel and some lemon juice before getting started. Bonus: the acid in the lemon juice also helps make a nice stiff meringue!
If you're frosting is still a bit warm and therefore a little loose, apply a couple of ice packs to the outside of the bowl with the mixer on medium-low. It should set up properly quite quickly.
This quantity of ingredients will make PLENTY of frosting, definitely enough for two small cakes.
After the buttercream is complete, I recommend letting hang out in the refrigerator, covered, for a little while before applying to your cake. This allows the mixture to mature a little bit in flavor, and get a bit cooler.
Cool (not cold) buttercream is much easier to frost your cake with! If it has been in the refrigerator for a little while, simply put it in the bowl of your stand mixer and use a paddle attachment to beat it to the consistency of smooth peanut butter.
Buttercream freezes exceptionally well. If you have extra frosting but don't have an immediate need for it, place it a ziplock bag labeled with the date, and pop it in the freezer. It will last comfortably for at least 6 months if well packed. If you plan to leave it in the refrigerator, it will last covered in the refrigerator for 2-3 weeks.
What is Swiss meringue buttercream anyway? It is the best of the buttercreams and I'll tell you why. French buttercream (whole eggs/egg yolks + cooked sugar syrup + butter) is awesome but super rich and the least stable of the bunch. Italian buttercream (egg whites + cooked sugar syrup + butter) is lighter and the most stable; it will stand up to heat the longest. German buttercream is made with a custard, and American buttercream (my least favorite BY FAR) is made with just butter and powdered sugar.
So, why use the Swiss style? Well, it's also very stable and is SMOOTH AS SILK. It's great for filling and finishing wedding cakes, piping, and can take on any number of different flavorings. It is more susceptible to warmer temperatures than its Italian counterpart, but my version holds up pretty well (I used to live in Florida. I know things about heat and humidity.). Another reason SMBC (Swiss Meringue Buttercream) is a winner, is that it's a bit easier to handle than Italian buttercream; pouring hot sugar syrup into whirling egg whites is not for the faint of heart, but it's also not impossible.
For a lovely little primer on the various types of buttercreams, read this Bluprint article.
Back to my Easy 1,2,3 Swiss Meringue Buttercream recipe.
Because this recipe is based on a simple 1:2:3 ratio, I always weigh my ingredients--makes my life a lot simpler. Don't fear the scale! It's a critical baking tool that I recommend every baker have. For more on digital scales, read this blog post I wrote on essential baking tools.
I'm also stickler for temperatures. When people suggest checking something by feel, I get it--touch is an important sense to develop in the kitchen, but I need a temperature (at least a close one) to associate it with. Benchmarks are everything. So, some say the sugar syrup for SMBC is ready when it feels like a hot bath (on a personal note, I'm not really a bath person, so this was not super helpful). You'll find a lot of videos that say cook the sugar syrup until it's warm and the sugar has completely dissolved. BUT WHAT TEMPERATURE IS THAT?
Traditionally this number clocks in around 160-ish degrees Fahrenheit. But, the crew at Serious Eats (actually its Stella Parks of BraveTart fame) who gave me a good tip: cook the sugar and egg whites to 175 degrees F. It's a game changer. Not only does this mean that the egg white sugar syrup is fully cooked, it means it's a little bit stronger and stiffer, and because you're about load up this bowl of meringue with several pounds of butter, you need a good, strong foundation.
The recipe provided above is my buttercream base, it tastes great on its own but I use this as the jumping off for lots of different flavors. Some flavor ideas include vanilla extract, salted caramel, dulce de leche, chocolate + sea salt, coffee, lemon mousseline, and more. The options are endless! We'll be sharing a future post about different ways to flavor buttercream, too.
Last but not least there's been a lot of talk about egg whites, but what about egg yolks? Don't worry, I've got you covered. Stay tuned for another post about how to use up leftover egg yolks, with a special emphasis and recipe on homemade lemon curd!