Swiss Meringue Buttercream Recipe (SMBC)

Renee from Renee Conner Cake Design teaches you how to make Swiss meringue buttercream. This is the buttercream she uses in her New Hampshire custom cake shop. With her step-by-step instructions, she shares her best practices for flawless SMBC:

  • weigh your ingredients
  • ensure grease free mixing bowl and whisk by wiping with lemon juice
  • refrigerate buttercream that won't thicken for a few minutes
  • apply light heat to buttercream that stays lumpy
  • have patience

She even makes recommendation for storing unused egg yolks for later use.


  • 4oz egg whites (use fresh and not packaged pasteurized egg whites)
  • 8oz granulated sugar
  • 12oz softened butter (unsalted!)
  • Pinch of salt
  • 1 to 2 Tbsp vanilla extract (or other flavoring; in this video I used about 1 tbsp)

*Tip: Wipe utensils and stand mixer bowl with lemon juice to make sure they are grease-free.

Step 1 Fill a small small saucepan with 1 to 2 inches of water and bring to a simmer.

Step 2 Add egg whites and salt to mixer bowl and whisk lightly.

Step 3 Add sugar and whisk to combine.

Step 4 Set mixer bowl over saucepan containing simmering water.

Step 5 Heat mixture and whisk continuously. Mixture is ready when it has reached 160°F. It will appear whiter in color and more opaque, and will no longer feel grainy between your fingers.

Step 6 Beat mixture using stand mixer on medium-high speed until stiff peaks form and mixture has cooled to room temperature. When it is ready, the mixture will be thick like marshmallow fluff.

Step 7 Scrape down whisk attachment and sides of bowl, and switch to paddle attachment.

Step 8 Set mixer to low speed and slowly add butter.

Step 9 Stop mixer and scrape down paddle and sides of bowl.

Step 10 Set mixer to low speed and mix until buttercream thickens and reaches a smooth consistency.

*Buttercream will likely go through stages as it mixes. Lumps may form, and it may curdle or liquify. Continue mixing. Eventually it will become thick and smooth.

Step 11 Scrape down paddle and sides of bowl. Set mixer to low speed and add vanilla. Mix to combine.

Things to note about this video:

  • The recipe will make about 3 cups of icing, enough to fill, ice & decorate a 6″ round (4″ tall) cake. If you are working with a larger size you will want to make an extra 1/2 to double batch.
  • The finished product looks a little yellow in the video, that is just from the lights over my kitchen prep space! In actuality SMBC will be an off white, to light cream color, and that is mostly from the vanilla! You can use clear vanilla instead, and/or add a touch of violet food color to offset any yellowness.


Comments (7)


Hi, I just recently discovered this buttercream and love it...thanks for the video. Quick question though...if you were going to add flavoring to it (like you mentioned at the end of the video) when would you add that and does it change the consistency. I've only ever added white chocolate ganache, but would the runnier stuff make the frosting, well, runnier?



@danyag- you really can add pretty much anything to this and it holds up very well. Some of the things I add- melted chocolate for chocolate buttercream (4-6oz for the measurements on this recipe, but you can add more or less), any kind of jam or fruit preserve (ex. 1/4 cup raspberry preserves!!) just add a little at a time to taste! Add caramel sauce, or dulce de leche for a really, unbelievably good caramel buttercream. Dissolved instant coffee... any kind of liquer. For a liquid like an extract or liquer I'd add a tablespoon at a time to taste, but as long as your not adding a lot it really should hold up okay!!

@Cassie2500- no, this buttercream does not crust...


Thank you SO much. I was a little bit scared to try SMBC without a candy thermometer, but the way you explained the process and outlined it step by step has given me confidence. Fantastic video. =)


Hope I get an answers on this  it's an older post. I tried my first smbc today from a recipe that is similar to this one. Cup cake jemma on YouTube. Anyway her weights are in grams but from what I can tell they r close. Anyway I know I made one mistake in that I didn't heat enough bc mine was still a bit gritty. I am not sure if this was why but the finished product came together but was so buttery tasting  I am not sure if this is bc of the initial mistake and not heating the sugar/egg mixture enough or if that is how it is supposed to taste  it is like twice as buttery as my regular buttercream in taste  any suggestions?