Strawberry Puree

1. Follow my recipe for strawberry puree without adding powdered sugar, ensuring it is well blended and strained through a fine sieve to remove seeds and residues, then let it cool completely.

Swiss Strawberry Buttercream

1. Place the egg whites with the powdered sugar in the bowl of the stand mixer and place it over a saucepan containing a little water heated on medium heat to cook the mixture in a double boiler.
2. Whisk continuously using a hand whisk and monitor the mixture, which should reach about 55°C/ 131°F and until the sugar is completely dissolved.
3. Return the bowl to the stand mixer fitted with the paddle attachment and beat at medium-high speed for about 10 minutes until you achieve a firm and cooled meringue.
4. Reduce the mixer speed and incorporate the softened butter pieces, then resume mixing at high speed until you obtain a thick and homogeneous buttercream. (The mixture may become grainy after adding the butter; continue beating until the mixture is smooth.)
5. Add the cooled strawberry puree, vanilla extract, and mix again for a minute to incorporate them, then add the food coloring if needed until you achieve the desired pink color.
6. Finish mixing with a flat spatula at low speed for 2 minutes before using your buttercream.