This swiss meringue buttercream is silky smooth and perfectly pipe-able. It is hands down the best sugar free frosting I’ve ever made and is worth the effort. Up your keto baking game with this amazing vanilla buttercream recipe. And it’s virtually carb free!
It’s January and you are all doing your best to get on track, stay on track, and avoid temptation. I totally respect that. I really do.
So why am I posting a recipe for something as decadent as Swiss Meringue Buttercream? Because, my friends, this is hands down the best sugar free frosting you will ever make, bar none. Silky, creamy, so easy to frost keto cakes and other goodies, and it holds its shape for days.
And even if it’s January and you are trying to be good, you deserve a sweet treat once in a while. Especially when it’s sugar free and keto-friendly!
I am a recent convert to Swiss Meringue, having made the American-style frosting all my life. While swiss meringue definitely requires a little more effort, both the flavor and consistency are worth it. It’s less tooth-achingly sweet but it’s silky smooth and the flavor is rich and buttery.
Heretofore, I despaired of making this gorgeous frosting because I knew that erythritol based sweeteners would re-crystallize too much. But having recently discovered that adding a little Bocha Sweet to my recipes helps keep them softer, I decided I wanted to tackle a sugar free Swiss Meringue recipe.
It. Was. Amazing. I felt like I had just won the keto dessert lottery. And conquering a sugar free frosting like this made me feel like I was ready for the big leagues.
What is Swiss Meringue Buttercream?
Swiss meringue is perhaps one of the most beloved frosting of professional bakers. It has an incomparable silky consistency and sweet buttery flavor, without being as tooth-achingly sweet as the standard American frosting.
It’s called “meringue” because it involves using egg whites to get a lighter, fluffier consistency. They are combined with sugar (or in our case, sweetener) and then gently warmed over a double boiler until the sweetener dissolves. Then they are whisked to stiff peaks.
You then add cubes of room temperature butter, which deflates the egg whites. For once, you actually want to deflate the egg whites so don’t panic! Once the whites and the butter are full combined, you truly have the most amazing silky frosting which pipes and spreads so well.
It also uses far less sugar or sweetener. A typical American buttercream will use upwards of 2 cups of powdered sugar, just to have the right structure. In many of my sugar free frosting recipes, I’ve gotten around this by using a little cream cheese to give it some structure without copious amounts of expensive sweeteners.
But this recipe for keto Swiss meringue buttercream uses less than a full cup of sweetener in the whole batch. And it’s enough to frost a 9 inch layer cake or about 18 cupcakes!
Sugar Free Frosting Research
Since Swiss meringue is a little trickier than your standard American buttercream, I knew I need to get the best tips and advice. I turned to some trusted dessert blogs and websites to learn just how to make it properly.
I found the instructions for Swiss Meringue from Handle the Heat to be clear and straightforward and so I followed those most closely.
I also read a great deal on what to do if it doesn’t come out right, which sometimes (often?) happens. My first batch curdled and I managed to rescue it based upon the tips provided on Serious Eats. The article was written by Stella Parks, of BraveTart and her advice was spot on.
Turns out that when it curdles, it may end up being fine if you keep whipping it. But if it won’t come back together, then it can mean that your butter was too cold. All you need to do is re-heat the whole mixture just a bit to bring up the temperature. Then you can keep whipping until it smoothes out.
Worked like a charm, thank you, Stella!
The second time I made it, I watched the temperature of my whites carefully, both while I was heating them and while I was cooling them. And I got perfect sugar free buttercream frosting from the start.
Advantages of Swiss Meringue Buttercream Frosting
Yes, it’s definitely trickier and more time consuming to make than standard buttercream. But it’s so so worth it.
I’ve already mentioned the incomparable taste and texture and the fact that it uses far less sweetener. But it holds up so well at room temperature and it doesn’t get overly greasy. It also doesn’t get crusty in the fridge and with the combination of Swerve and Bocha Sweet, it won’t recrystallize at all.
It can be made ahead and refrigerated for a day or two and can be frozen for up to 2 months. To make it smooth and creamy again, just let it come to room temperature and beat it on low until smooth.
Yes you can add other flavors and additions. I have yet to try that though but I will report back when I do!
So are you ready to up your keto baking game and give this amazing sugar free frosting a try?
Sugar Free Swiss Meringue Buttercream Frosting
Ingredients
- 4 large egg whites
- ½ cup powdered Swerve Sweetener
- ⅓ cup Bocha Sweet (allulose or xylitol may also work)
- 1 cup unsalted butter, room temperature cut into tablespoons
- 1 teaspoon vanilla extract
- ¼ teaspoon salt
Instructions
- Make sure the bowl of a stand mixer is very clean and set over a pan of barely simmering water. Add egg whites and both sweeteners.
- Whisk gently but constantly, until the sweeteners have dissolved and egg whites are hot and slightly frothy. They should reach about 150F on an instant read thermometer.
- Transfer the bowl to the mixer and attach the whisk. Whip the egg whites at medium high speed until they are thick and glossy and the bottom of the bowl is no longer warm, anywhere between 5 and 10 minutes. The temperature should be about 90F on an instant read thermometer.
- Start adding the butter cubes one at a time until full incorporated and the frosting is smooth and creamy. Turn stand mixer to medium low and add the vanilla and salt until combined.
- Spread or pipe on your favorite keto cakes and cupcakes! This frosting also freezes really well. Let it come to room temperature again and rewhip lightly before frosting.
- NOTE: I know I will be answering this question over and over so let me just say it straight up. You need the two different sweeteners here! A combination of an erythritol based sweetener, such as Swerve, and one that keeps things softer, such as Bocha Sweet, xylitol, or possibly allulose, is necessary to achieve the correct consistency.
Notes
Felicia says
Can this tecipe be nade daury free by replacing the butter with non-dairy butter sticks?
thank you!
Carolyn says
Very doubtful but you are welcome to experiment.
Lucky says
I just tried this and it works great. I only had powdered Truvia so just used about 2/3 cup of that and crossed my fingers.
I appreciate that you explained that the whites will deflate because the texture sure did change from beginning to end on this.
Great recipe and explanation. Thank you.
Carolyn says
Glad it worked out!
Marie Campos says
love this recipe! just wanted to share that i have made this with all Allulose for the sweetener and the texture was still perfect! it went great with your chocolate mayonnaise cake recipe.
Julie says
W O W! This recipe is worth the little bit of extra effort. I made a half batch with my hand mixer, carton egg whites (2 tablespoons equivalent per fresh egg white), and allulose instead of bochasweet. It’s perfect. I spread it onto an almond flour sheet cake.
Margaret Henry says
I can’t find the metric conversion button that is usually present on all your recipes. I am hooked and I never used US customary anymore! Ever! Especially with keto sweeteners. It never says packed or scooped brown sugar so without the weight how do you know? Help! How can I vary the flavors?
Carolyn says
I will try to fix this one soon… but unless a recipes SAYS packed, you should NEVER pack your ingredients.
Alana Brown says
Can I add coloring to this? I am looking to make a marbled cake. Thank you!!
Carolyn says
Sure.
Monica Kincaid says
It looks delicious. Does the cake need to be refrigerated all the time? I have an outdoor birthday party next week. I am in Miami Florida
Carolyn says
It really depends on how hot it will be…
Adri says
This was SO good. I’ve never tried making a swiss meringue buttercream before, so I was a little hesitant about the double boiler but it worked out great. I used a thermapen to check temp often. Super silky and delicious.
I oversalted mine a tiny bit, but I kinda like things extra salty anyway. It made me wonder if this could be made with a salted caramel flavor. Maybe with an allulose caramel in place of the bocha/xylitol/allulose?
Sarah says
So I’m having a hard time with this recipe. It does not make very much icing. On top of it my mixing bowl just cracked in 5 places due to the heat…
Carolyn says
The metal bowl of a stand mixer won’t crack… what kind of bowl did you use? Additionally, this recipe makes enough frosting for at least 16 cupcakes. Did you use carton egg whites rather than fresh? Or small egg whites, rather than large?
Denise says
made this today to frost a three layer fudge cake. I doubled the recipe and even had a little left over to frost some cupcakes I also made.
This buttercream is a dream to work with! So smooth, buttery, and creamy, and it doesn’t “break”. Spreads easily, pipes easily, and is so delicious!
Carolyn says
Yay! Isn’t it lovely!
Terrence says
I made this yesterday (with the classic birthday cake recipe) for a non-keto friends birthday. She does avoid sugar so she asked me to make her a cake. All I can say is WOW. The icing is amazing and we all licked the plates clean. I was a bit nervous trying it because of all the comments, but I followed the directions to a T and it came together beautifully. Thank you for this recipe and all the work you do!
Faatimah says
hi can I use only xylitol to substitute both the serve and the bocha. I only have xylitol.
Carolyn says
You can certainly try. I am not sure how it will work out.
Susan Kennard says
I need to update my previous comment! I was the one who gave the recipe 4 stars even though I wrecked it. Curdled, then soupy, then curdled again. I abandoned the frosting and left it in a curdled mess in the fridge and was going to start on the Cream Cheese icing. 15 minutes later I took the icing out of the fridge and gave it one last try with the mixer, and it came together and became icing!!!! I stopped mixing as soon as it came together in case it was going to change states again. Added a teaspoon of orange extract and now it on the Chocolate Mayonaisse Cake. It does not look fluffy and perfect, but it is good enough.
Carolyn says
You still only gave it 4 stars… 🙂
Did you not read the tips about how to rescue it? Because what you did (the fridge) is exactly how to rescue it.