Italian meringue buttercream is my all-time favourite kind of buttercream. To explain why, I’m going to have to explain what it is, and why it’s different from other buttercreams.

Let’s start with the different types of meringue.
There is French meringue, Swiss meringue, and Italian meringue.
A French meringue is made by whisking egg whites with granulated sugar until the sugar dissolves. A Swiss meringue is made by heating the egg whites and sugar over a bain marie (a glass or steel bowl on top of, but not touching the simmering water) until the sugar dissolves, and then whipped up in a stand mixer to a fluffy meringue. An Italian meringue however, is made by boiling a sugar syrup to 117C/243F and slowly pouring that into a running stand mixer that is simultaneously whipping up the egg whites. Once all the sugar syrup is in the mixer, the mixer is turned on high and then the meringue is whipped until cooled. Italian meringue is the most stable and safe to eat.

Now, let’s talk about Italian meringue buttercream.
It’s exactly what it sounds like. It starts with a an Italian  meringue, and then you add butter. People may think that Italian meringue buttercream is a little tricky, so let’s get down to the basics and potential troubleshooting if things go wrong.

1. Your bowl and whisk must be completely clean in order to whip up egg whites. A good way to ensure that is by taking some lemon juice on a paper towel and wiping that around the sides and bottom of the bowl, as well as each individual wire on your whisk. If any fat gets in there before the meringue has been established, it will have troubles whipping up.
2. A sugar thermometer is required. You could eyeball it… but it’s probably better not to. You could’ve just made simple syrup and not know it — or caramel if you’re not watching your pot.
3. Start whipping your egg whites when your sugar reaches 112C/234F. By the time your sugar syrup reaches 117C/243F, your egg whites should be ready for the sugar. You will know it’s ready because the egg whites will have foamed up to very soft peaks.
4. Avoid sugar burns by lowering your mixer speed when you pour the sugar syrup into the bowl. Nobody likes a gnarly sugar burn! Be careful when pouring your hot syrup.
5. TEMPERATURE IS KEY! If your butter happens to be very cold, add it when the meringue is warm, but not hot to the touch. Check this by touching the side of your mixing bowl. If your butter is soft, throw it in when your meringue has cooled completely. If you’ve managed to underestimate the temperature of the meringue and it completely melts all your butter, you can try sticking it in the fridge for a few min until it is slightly cooled, and then attempt to whip it up again. If your meringue has cooled down too much and your butter is too cold well… when in doubt, try to whip it out. Aim for soft butter and a completely cooled meringue for a foolproof buttercream.
6. When you think you’ve done it all wrong… you’ve added the butter and it’s starting to curdle. No worries!! You’re actually on the right path. The buttercream usually appears to curdle right before it all comes together. So if you’ve made it this far, congrats! Just keep whippin’ it.

Follow these tips and I’m sure you can achieve this luxurious buttercream. It’s worth it, trust me. This buttercream can be easily flavoured with coffee extract, melted chocolate, peppermint oil, or anything really. I usually just add a little Madagascar vanilla bean paste, and it tastes amazing.

This buttercream is perfect for any kind of cake! For cake recipes to use this buttercream with, check it out here. Enjoy!! 😜