Swiss Meringue Buttercream

Like a brown-eyed baby born with blue eyes, all my buttercreams are born vanilla. The only exception to that is my brown sugar buttercream because it doesn’t follow the recipe below. Make up a batch of vanilla buttercream and imagine the possibilities. You can add some melted white or dark or milk chocolate, any kind of homemade fruit puree (which I prefer over jam), crushed candies or nuts, zest of orange or lime or lemon, freshly made caramel…really, anything! Just avoid anything with too much liquid in it, or cream cheese (I’ll tell you how to make that further down in this post) as this can break your buttercream.

Vanilla Swiss Meringue Buttercream

Printable Recipe

Makes a lot of frosting…enough to frost 24 cupcakes with big swirls, or to fill and frost a cake. Recipe can be halved or doubled with no problems, I have even made 1.5 batches of this recipe many times. If you have left over frosting, you can freeze it in an airtight container for up to 2 months or store it in the fridge for a week. To reconstitute it, take roughly 1/3 of the cold buttercream and microwave it until it’s warm and soupy (not hot). Add the warmed buttercream to the cold buttercream and rewhip with the paddle attachment until silky and smooth.

Okay, this is gonna get super easy.  Are you ready?  Just remember… 10, 15, and 20 (in that order) and you can make this buttercream anytime without even looking at the recipe.  To halve of course, would be 5, 7.5, and 10.  I’m talking ounces here, so get out your trusty kitchen scale.  If you don’t have one…go buy one.  With weight, you will NEVER go wrong with this recipe….

TLB Tip: Before you begin, wipe your mixing bowl and attachments (paddle and whisk if using a stand mixer) with lemon juice soaked paper towel.  Just squeeze some lemon juice into the bowl and wipe with a paper towel, use that same paper towel to wipe down your mixing attachments.  This will remove any residual oils or grease left on the bowl that would prevent your meringue from whipping up into silky oblivion.

You will need:

10 ounces of egg whites

15 ounces of granulated sugar

20 ounces of room temperature unsalted good quality butter (organic or European butter will give you the best results because it doesn’t have any artificial flavorings added, which can give your buttercream a funny taste)

pinch of salt

1/4 cup pure vanilla extract (not imitation)  you can also use vanilla bean seeds scraped from the pod for vanilla bean buttercream.  Mmmmmm

TLB Tip: Don’t go separating eggs, unless you really want to. Instead, go to the egg section of the grocery store and purchase liquid pasteurized egg whites. It’s so much easier than wasting egg yolks. I use these liquid egg whites for my buttercreams, royal icing, white cakes, lemon cakes, chiffons, angel food cakes, marshmallows, meringues, french macarons, and more. It’s great stuff!

You will need a medium sized sauce pan that can fit your mixer bowl into the top portion of it (test to make sure it will rest on top comfortably).

Put a couple of inches of water into the saucepan and then put your bowl on top for a second or two, remove the mixing bowl and check to see that there isn’t any water on the bottom of the bowl.  You want the bottom of the mixing bowl close to the water but not touching it.  Pour some water out, if needed.

Bring the water to a boil over medium high heat.

Set the mixing bowl on your scale and pour 10 ounces of egg whites into the bowl of your stand mixer, clear out the scale and then add the 15 ounces of sugar (you can use organic sugar with ease here because its cooked, the texture wont affect the buttercream). Add a pinch of kosher salt to the mixture.

Lightly whisk the egg and sugar and salt together until they are mixed together and the sugar is no longer clumped on the bottom of the bowl.

Place the bowl with the egg mixture over the boiling/simmering water and whisk constantly until the mixture reaches 160 degrees on a candy thermometer, or until the sugar is completely dissolved and the mixture begins to look foamy.

TLB Tip: It’s important that all of the sugar gets dissolved so you don’t end up with grainy buttercream, so for best results, use a thermometer.

Carefully remove the bowl from the saucepan (with a pot holder on your hand) and place on the mixer.  Using the whisk attachment, turn mixer on to medium high (#8 on my mixer) until most of the steam is gone, then, crank up the mixer all the way to high (#10 on my mixer) and set a timer for 10 minutes.

If using a stand mixer, you can use these 10 minutes to practice good mise en place and clean up and get your 20 ounces of butter ready.  For reference, if using stick butter, that’s 5 sticks of butter.  Unwrap the butter, measure it out, and cut and the sticks in half, if using.  Some recipes will tell you to cut the butter into little tiny cubes, but that really isn’t necessary, it just makes the process go a little faster.  In fact, you can even use cold butter, yes cold, but it will take much longer for the buttercream to come together.

When the 10 minutes is up, the meringue should be beautifully white and fluffy, doubled in size, and the bottom of the bowl should be pretty close to room temp.  Stop the mixer, bang the whisk against the bowl several times to dislodge any meringue caught in it and switch to the paddle attachment.

If your mixer can handle the volume, add the butter in all at once.  I have a professional 6 qt kitchenaid and it’s a little much for my mixer (I usually double this recipe) so I start on the lowest speed and gradually throw in the butter so it doesn’t overflow.  Mix on low speed (#2 on my mixer).

Now is the time to NOT panic because your buttercream is going to look ruined and wrong but trust me on this, it’s just fine.

Stage 1: When the butter begins to mix in, the buttercream will become loose and soupy looking.  It’s just the air in the meringue beginning to get weighted down from the fats in the butter and it’s totally normal.  Scrape down the bowl if necessary and then continue to mix on low speed

Stage 2: Past the soupy stage, the buttercream may look curdled (sometimes it wont depending on the temp of the butter used).  This too, is just fine.  It’s just the butter beginning to break down and mix in, if you see this, you’re doing it right!

Stage 3: Right after the curdled stage, a miracle will happen.  All of a sudden you will look in the bowl and see the buttercream has become thick and creamy and is beginning to pull away from the sides of the bowl.  This is called emulsification…and it’s a beautiful thing. Success!  Keep mixing on low speed a couple minutes more until its very silky.

Add in the vanilla extract on low speed and mix again until combined.

Taste the buttercream…it should taste like silky room temperature vanilla ice cream.  YUM.  Now you can add in any additional flavorings on low speed if desired.
How to make Cream Cheese Swiss Meringue Buttercream:

You would think that you could just add some softened cream cheese to a batch of SMB, but sadly, you can’t.  Believe me, I’ve tried it…many, many times. The best method for me is to follow a recipe for plain old cream cheese frosting and sub in the SMB.  Like this one, courtesy of “Miette” in San Francisco, which can also be doubled.

Cream Cheese Frosting
Makes about 3 cups

1/2 cup plus 3 tablespoons unsalted butter, room temperature
1 cup sifted, powdered sugar
2 cups (1 pound) cream cheese, room temperature

Now, instead of using the unsalted butter and the powdered sugar, you will substitute your prepared Vanilla Swiss Meringue Buttercream instead.

Start by beating the room temp cream cheese until completely smooth, then add in the 1/2 cup plus 3 tablespoons Vanilla SMB and mix on low speed just until combined. Done!

This is my Caramel Swiss Meringue Buttercream which was born as Vanilla until I added some homemade caramel to it and a pinch of fleur de sel (sea salt)

Caramel Swiss Meringue Buttercream