PEANUT BUTTER SWISS MERINGUE BUTTERCREAM
- 60g egg whites
- 100g granulated sugar
- pinch of salt
- 225g (2 sticks) unsalted butter, cold, cut into small cubes
- ½ tsp vanilla bean paste
- 150g smooth/creamy peanut butter (processed peanut butter is best, natural may seize your buttercream)
- Place the egg whites, sugar and salt in the bowl of a stand mixer or a heat proof bowl. Place over a pot of simmering water, ensuring that the water does not touch the bowl. Heat, whisking constantly, until the mixture registers 160˚f / 70˚c on a thermometer and the sugar has dissolved. Carefully transfer the bowl to the mixer, and fit with the whisk attachment. Whip the egg whites on high until they are snowy white and fluffy, 8-10 minutes. Add the butter one chunk at a time. The mixture may look curdled - but just keep mixing! Once all the butter is incorporated, mix on high for a further 10 minutes.
- Once the buttercream has finished mixing, and is smooth and silky, add in the vanilla bean paste and peanut butter. Mix for a further 2-3 minutes, then switch to the paddle attachment and mix on low for one minute to remove any air. Fit a piping bag with a small french star tip, and fill the bag with the buttercream.
- Pair up the macaron shells, and pipe a round of buttercream blobs on one half of each pair. Top with the second shell. Smooth any buttercream that is sticking over the edges with your finger, then roll the macarons in sprinkles so that the sprinkles stick to the buttercream. Macarons taste best if you 'mature' them in the fridge overnight to let the flavours meld, but they are perfect eaten immediately too! Store leftovers in an airtight container in the fridge.