1. Preheat the oven to 180°C (350°F). Line a muffin tin* with 12 cupcake paper liners*. In a medium bowl sift together flour, baking powder and salt. Set aside. Wash the strawberries, dry, and chop them into small pieces.

2. In the bowl of an electric mixer fitted with the paddle attachment, beat the butter and sugar until light and fluffy – this can take about 4-5 Minutes. Add the egg and vanilla extract and beat until incorporated. Add the flour mix in three parts, alternating with the milk. Beat until combined after each addition. Gently fold in the chopped strawberries.

3. Divide the batter evenly among the prepared liners. Each paper liner should be about two-thirds full. Bake the cupcakes for about 20 minutes or until the cupcakes are golden brown and a toothpick inserted into the centers comes out clean. Take them out of the oven and let them cool inside the muffin tin for about 5 minutes, then remove them and let them cool down completely on a wire rack.

4. For the buttercream add the egg whites and sugar to a large heatproof bowl. Place on a pot with simmering water. Mix the egg whites and sugar constantly and bring it to a temperature of 71°C (160°F). If you don’t have a thermometer, rub the mixture between your fingers to test – if the sugar is dissolved completely, you’re done. Remove the mix from the heat and add it to the bowl of a kitchen machine and mix until you get a thick, white meringue that has cooled down significantly (handwarm only) – this process can take up to 10 minutes.

5. Next, add the butter in small pieces, one after another, and continue mixing. If the buttercream looks a bit curdled or soupy, the temperature difference between butter and meringue was too big. This is easy to fix, though! Warm the whole bowl a bit and then mix until you can’t see any bits anymore. Then cool the buttercream for some time in the fridge and then mix again – this should fix any textural problems. If everything is fine, add the vanilla extract and mix it in. If you want a buttercream with larger strawberry pieces, fold in the strawberries carefully. If you aim for a smooth (and more pink) buttercream, throw the strawberries into the bowl and mix everything until smooth.

5. Fill buttercream into a piping bag with a large round tip or a star tip – with bigger strawberry pieces I would recommend the round tip, otherwise the pieces can get stuck. Pipe a swirl of buttercream on each cupcake and decorate with sliced strawberries (optional). Store in the fridge until ready to serve.

Note: If your cupcakes are not served immediately or if they have to wait for a while, do not decorate with sliced strawberries right away – they look a bit sad after a while. Do that shortly before serving.