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.
Andย 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
- 1/2 cup powdered Swerve Sweetener
- 1/3 cup Bocha Sweet (allulose or xylitol may also work)
- 1 cup unsalted butter, room temperature cut into tablespoons
- 1 tsp vanilla extract
- 1/4 tsp 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
Kate says
Hello Carolyn,
Firstly thank you again for your tireless efforts in making this way of eating enjoyable! My blood sugar and my tummy thank you ๐
I was wondering if you had some insight into an issue Iโm having. Iโve made this recipe twice, and it seems to fall flat after adding in the butter. As in it looses its air and flattens.
The egg whites whip up wonderfully, I have lovely voluminous fluffy egg whites. The butter goes in fine, no issues with being grainy or soupy or anything. But by the time itโs done it has just.. shrunk. Like all the air has gone out of it and itโs just creamy fat. Instead of 4 cups of SMB, I have 2 cups. Its more like flat buttercream. Itโs even less fluffy than my creamed butter when Iโm creaming for cakes! This canโt be right, can it? I mean it tastes fine, but is dense and rich instead of fluffy.
I have a good thermometer and check everything is room temp before, and doing good along the way. Iโve tried whipping for another 5-10 minutes but that didnโt do anything. I thought maybe things got too warm so I refrigerated it a while and tried whipping it up again, but to no avail.
I canโt seem to find any answers about this elsewhere. Just on how to fix SMB that is too loose/runny or grainy or looking curdled. No info about SMB that has lost all of its fluff/air. I canโt help but wonder if I canโt find an answer elsewhere, perhaps it has to do with the sugar free component that is causing it? Any ideas? Thank you!
Carolyn says
Are you using carton egg whites or fresh? When I tried carton egg whites once, I ended up with something quite a bit more dense. I don’t recommend them. Also, what sweeteners are you using? And finally… at what point along the way, when adding the butter, does it go flat? Maybe if we can’t figure out the problem, you should stop adding butter just before that point.
Are you at elevation by chance?
Kate says
Thank you for the reply! Iโm using fresh from the egg whites, at room temp, (with everything they touch painstakingly triple cleaned so theyโll whip up). I am using the confectioners Swerve and granular Bochasweet, as written. Not at elevation (quite close to sea level actually).
Iโm not sure exactly when it goes flat, but I think itโs while adding the butter. I think oh sure itโs supposed to go down in volume a bit, because itโs emulsifying. But then it just keeps going, and by the time all the butter is in it has shrunk white a bit. Like I said I tried whipping it more but that seems to just make it worse, until itโs very flat. I was under the impression that you canโt over whip SMB, but maybe thatโs wrong? Do I need to add the butter faster? (Butter is all cut into small cubes, a room temp, and I add in one cube at a time.)
Carolyn says
I don’t know why, but I think you may need less butter in total. It’s not scientific by any means, just based on how you describe it. yes, it will go down a lot as you add the butter but it should end up like a silky frosting…
Jme says
Oh I forgot to ask how to make this in chocolate? Or can I? Sorry not a baker, just a recipe duplicator๐
Carolyn says
Check out how I made a chocolate version here: https://alldayidreamaboutfood.com/keto-marble-cake/
Jme says
I made this today hoping it was all I wanted in a keto frosting and it absolutely was!!! I did use a swerve vanilla cake mix for ease , added lily’s milk chocolate chips, and it was fabulous. I also used 1/2 bocha sweet and 1/2 So Nourished eryth/monk fruit. No problems with that.
I’m so grateful for you Carolyn and all your recipes. It makes life on keto very enjoyable!
kaidan says
It is so fun to bake because it makes you better at coking as well as it does baking.
kaidan says
I a kid and I love baking and you are the only person who inspires me to bake the cakes and cupcakes that I bake almost daily for fun and entertainment.
Joanna VM says
Hi there. I think I’m going to try this recipe for a double layer sugar free cake. So icing between the two 8″ rounds and over the outside. Will one batch make enough?? Or should I double it?
Carolyn says
One batch should be enough for that size cake.
Nina Christophi says
Just made a batch of this up but added lemon juice. Worked a treat and tastes amazing! Made a birthday cake so with this frosting and the sugar free lemon meringues i made it will look and taste great. Thank you!
Carolyn says
Nice! Sounds like a tasty treat.
Yolan says
Iโm so excited to make this recipe! I have swerve confectioners sugar and plan to use either xylitol, allulose or wait for an amazon order of bocha because I canโt find it in stores. If I use xylitol or allulose, do I use granulated or powdered? Iโm guessing powdered but since you mentioned something about the texture I want to be sure. Thank you for sharing this!!
Carolyn says
You can use the granular since it gets whisked into and dissolved in the egg whites.
Bernadette says
I almost chickened out, but Iโm so glad I tried it! I looked through all of the comments to see if anyone had tried carton egg whites but I gave it a go and it worked perfectly! I just hate having to figure out what to do with extra yolks and I hate to throw food away, so I was anxious to see if this would work with egg whites from the carton. Yahoo! Delicious cupcakes for our sonโs birthday!
Jenny says
This recipe was a lifesaver for my toddlers birthday party! We don’t let her have sugar, but I still wanted to have a cute birthday cake. We ended up going with a Beauty and the Beast themed birthday party and this icing worked amazingly as the dress swirls for a stand up Belle cake! They also made adorable little red roses for the mini cupcakes I made. I was SO IMPRESSED at how well this frosting worked!! Thanks for saving the birthday party Carolyn!!
Lindsay Lingenfelter says
Holy crap. Absolutely fantastic. First time making it and I managed to pull it off and I could eat the entire batch with a spoon. I had mine too cold, so I mildly heated it and it whipped up perfectly in seconds. Unbelievable. Granular erythritol and granular xylitol is what I used.
Anu says
This was a mission and a half, but in the end it all turned out alright! ๐ The instructions are fantastic and very clear, and I really enjoyed the whole process. although my arm was aching at the end of it (no stand mixer here, just a handheld electric whisk, and no bain marie, so I used a glass bowl on top of a saucepan with simmering water). I have a very trusty instant read thermometer so I thought I was measuring everything carefully, but I think my egg whites and sweeteners may have still been a few degrees too hot when I added the butter, as the result was a bit soupy when all the butter was added in. No matter though, I left it in the fridge for about 30 minutes, but I guess my fridge runs a bit too cold as it came out solid and greasy… oops! Still not one to give up, I put the bowl back on top of my makeshift bain marie and let it melt at the edges and then whipped it again. This time it was perfect! Just the texture I had hoped for, and no graininess or soupiness… phew! I would love to try this as a chocolate flavoured buttercream, but I have no idea where to begin. Thank you so much for this wonderfully written recipe, it was most satisfying to make. I used this frosting in your margarita cake for my husband’s birthday this weekend, and it went down a treat ๐
Carolyn says
If you want a chocolate version, see my marble cake recipe. The thing about SMB is that it is tricky to get the temp perfect from the get-go but you can adjust and it still works out!
Anu says
Oh my goodness, you mean this one right?
https://alldayidreamaboutfood.com/keto-marble-cake/
I will absolutely make this soon, weekend after next – this looks incredible! Thank you so much, you made my day.
And yes, I’m delighted to discover how forgiving SMB is ๐
Carolyn says
Yes, that’s the one!
Dani says
This is literally the best frosting I’ve ever had. So light and just perfect. I added cocoa powder and a bit of instant coffee and it’s absolutely spectacular. Thank you!
monika says
Will this hold up without Bocha?
Carolyn says
Sure, but it will likely re-crystallize again as it cools. Who wants gritty frosting?
Morgan says
Any chance this would work with granulated swerve (instead of the bocha sweet) with the powdered swerve? I want to make this this weekend, and that’s all I have on hand.. with social distancing, I’d rather not head to the store unless absolutely necessary! If it won’t work though I’d head out. Hopefully you’ll see this in time!
Carolyn says
Technically yes it will work… but then it will re-crystallize quite badly when refrigerated. I don’t recommend.
Linda says
Hi Carolyn,
I’m SUPER excited to try this for a cake I’m planning to make tomorrow (your chocolate mayonnaise cake). I was discussing it with my mom and she asked me if it was like 7 minute frosting and I said no but it seems similar. I ‘dwondered if you’d ever attempted 7 minute frosting and if so, did it work?. I’m wondering if it requires ‘real’ sugar to do its magic. If you haven’t had it, it’s amazing – it’s almost marshmallowy in its consistency. It’s sweet but not cloying.
Thanks,
Linda