Swiss Meringue Buttercream (SMBC)

Mastering Levelled Recipe

2/1/20245 min read

cupcakes on white ceramic plate
cupcakes on white ceramic plate

Mastering Levelled Recipe - Safely works with unpasteurized Ingredients, and more complex procedures/equipment.

A smooth, velvety, less sweet buttercream that melts in your mouth! It holds its shape beautifully when piping!

Based off of a meringue and butter, you bakes with this buttercream do need to be kept in the fridge and out of the heat/sunlight as it will melt. It can stay out at room temperature at most for an hour (depending on the thickness and size of the cake) to come back to room temperature to consume in its velvety state.

This recipe makes approximately 6 cups of buttercream which is enough for about 24 cupcakes and a 3 layer 6 inch cake (depending on the complexity of the design).


  • Food Thermometer

  • Mixer

  • Bain de Marie (skill)


  • 5 egg whites, must be at room temperature

  • 452g unsalted butter, must be at room temperature & cubed (2 cups)

  • 300g granulated sugar (1 & 1/2 cups)

  • 1 pinch of salt

  • 1 teaspoon vanilla extract


  • Measure, place and gently mix with a whisk the egg whites, sugar and salt in a heat resistant bowl
    *I use my stainless steel mixer bowl*

  • At medium heat, simmer water in a saucepan. Place your Mixture bowl over this sauce-pan while making sure that the water does not touch the mixture bowl.

  • Whisk the egg whites to prevent the egg whites from cooking. Continually whisk until the mixture reaches an internal temperature of 160ºF for approximately 1 minute.
    *This step is REQUIRED as the egg whites get pasteurized at this temperature, making them safe to consume*

  • Once 160ºF is reached and sustained, carefully transfer the bowl to a stand mixer, mix at Medium speed with a whisk attachment until you get room temperature, glossy, stiff peaks - this takes me approximately 20-30 minutes.
    *To help: the color of the mixture turns translucent to opaque white*
    *Bringing it down to room temperature is crucial! If too warm it will not only take longer but change the consistency of the buttercream when incorporating the butter in the next step*

  • Switch to a paddle attachment. Turn the speed to low and add your cubed, room temperature butter. Let the butter incorporate before you add the next piece.
    *At times, the mixture can look curdled like cottage cheese but patience! This happens to me all the time - let it continue to mix and voila!*

  • Once all the butter is added, add the vanilla extract.
    *To get a smooth buttercream, to eliminate air bubbles, let your buttercream continue to mix on low speed for additional time - about 10-15 minutes.

  • Transfer it to a piping bag or use straight onto your cakes!


  • Other bakers have had success freezing or placing their SMBC (Swiss Meringue Buttercream) in the fridge, then thawing it when required. I have not - I do not freeze or place in the fridge! I have found the consistency changes which complicates the piping, coating and use during decore time. Thus, from my personal experience, I would not recommend storing it and instead make the batch fresh when required for the most optimal texture!!


  • Play around with flavouring by replacing the 1 teaspoon vanilla extract with another extract.

  • Powdered flavouring is an incredible option! Think of Freeze dried & powdered Fruits, chocolate powder, cookies blended and in a powder etc. The quantity depends on the boldness of flavour but be mindful of adding too much as it can change the consistency so start with 1/4th of a cup!

  • Thick pastes like Nutella, Cookie Butter, Nut Butter, ganaches etc. work well too as they do not introduce too much additional liquid. The quantity depends on the boldness of flavour but be mindful of adding too much as it can change the consistency so start with 1/4th of a cup!

  • Fresh Fruit, Jams, Curds are a bit tricky as they do contain more liquid than the previous suggestions. Remember, a little goes a long way. I would love to suggest quantities to start with but it all really depends on how runny these options are.
    *What Baci would do instead: Use these lovely textures and flavours as cake fillings! Carefully add swiss meringue lightly on the surfaces of your cake where the filling would be placed, and create a wall of butter cream on your bottom layer. This will prevent the cake from spilling these contents and make it impossible to coat the cake! It has occured me!*
    *When working with fresh fruit, I like to remove additional liquid by chopping them up into small pieces/cubes and taking a paper towel to squeeze them slightly!*


  • Coloring works best with powdered or gel food coloring. The depth of color will depend on the quality of your brand.

  • When to color? It all depends - do you need multiple colors or a single color? Regardless, once you have flavoured and completed the SMBC process, that is when I would do it. In other words, the absolute last step!

  • PRO TIP: SMBC is notorious for being a bit more difficult to color than say American Buttercream (ABC) as American Buttercream is more dry due to the powdered sugar. Thus, to intensify SMBC, remove about 1/4th cup of the total buttercream batch and add your coloring, mix and heat in 5 second intervals in the microwave to a maximum time of 15 seconds (if needed). It will liquify but you will notice the color is more vibrant! Add this bold colored SMBC liquid to the rest of your buttercream.
    *You NEED to remember that if you are splitting the whole batch of buttercream into smaller colors and use the above technique, you will need to heat less than the 1/4th described above. Think about it as a ratio - ONLY heat up at least 1/5th of the amount you plan on coloring to ensure that once you add that vibrant heated amount, it will not melt the rest of your buttercream!
    Ex. If I split my Buttercream in 4 colors, I would grab one of those quantities (1/4th of my batter) and heat up at most 1/5 of that 1/4th! Then repeat if need be*


  • As with macarons, specific steps will save your sanity. Wipe down the heat resistant bowl where you will place the egg whites with vinegar to remove the potential fat residue that may have been left from a previous bake (ex. butter)

  • I have noticed it is so much easier to separate a cold yolk from a cold egg white! It helps avoid the egg yolk breaking in the process. Thus, if you wish to separate your eggs cold, you can do so, just place them in separate containers after, and before using the egg whites, bring them down to room temperature!

  • Forgot to get the eggs to room temperature? Happens to me all the time! Place the eggs in a bowl of hot water and within 5 minutes or so (double check by touching them and if need be change their water if they're still not at room temperature!). Then, carefully separate your eggs!
    *TIP: Have three bowls when seperating your eggs: one your heat-resistant bowl, one bowl for yolks and third where you will place your egg whites. Separate one egg at a time over the designated egg white bowl. Place the yolk that you have separated in the designated yolk bowl. Then, transfer your clean egg white into your heat-resistant bowl! Repeat 5 times!

  • Why do this? It's a tad less frustrating having ONE egg white be contaminated with a broken yolk and used for something else later on, than separating all your egg whites and having the final one contaminate ALL your hard work and have to redo and discard 2+ eggs for something else! Yes, it has happened to me and this I learned the hard way!*