Italian Meringue Buttercream
While this buttercream recipe may look intimidating, we promise it's really quite simple! Read through the process fully before starting so you know what to expect. This is the signature buttercream recipe that we use for many of our macarons! Enjoy!
113g egg whites (room temperature)
454g butter, cubed. (room temperature)
Place the water in a pot and pour the sugar into it. Do not mix. Turn the temperature as high as it will go and using a probe thermometer, watch until it hits 236°F (we will be cooking it to a final temperature of 244°F).
While the sugar is boiling and getting up to temperature, place your egg whites in the bowl of a stand mixer. Make sure the bowl and a whisk attachment are REALLY clean, with no residual fat from anything else.
Once your sugar syrup reaches 236°F, start whipping your egg whites on high speed. You want them to be nice and whipped before adding the sugar syrup, think soft peak stage.
Once the sugar syrup hits the final stage of 244°F, remove it from the stove and slowly pour it into your whipping egg whites (with the mixer still running). Aim for the small gap between where the whisk and the bowl don't touch, so as to avoid flinging hot syrup everywhere.
When all the syrup is in the meringue, leave it whipping at high speed until the bowl has become only warm to the touch. This should take at least 5-10 minutes.
Now that the meringue has cooled down, you can start adding your butter piece by piece. Again with the mixer still running, but you can do this on medium speed.
Once all the butter has been added, scrape down the bowl and give it one last mix.
Your final result should be a smooth, glossy buttercream!
It is at this point that you can add any flavourings that you like. Vanilla, spices, fruit purees, flavourings etc!
Freeze any leftover buttercream for later use. To use it again, whip at high speed once it has softened to room temperature. It may look like it has split, but just keep whipping and it will com together again.