In a pan on medium heat, cook strawberry puree for about 6-8 minutes and let it cool completely. It should be at room temperature before it can be used further in the recipe. This cooking step ensures that the strawberry flavors and colors get concentrated.
1 cup Strawberry Puree
In a large bowl, add four egg whites and fine granulated sugar, and cook using the double boiler method by stirring continuously for about 2-3 minutes or until the sugar completely dissolves and the mixture turns pale white. If you use a thermometer, the temperature should range between 100 to 120 F. Remove from the boiler and let it cool for 5 minutes.
4 Egg whites , ¾ cup Sugar
Next, using a handheld beater, beat the egg-white mixture to form stiff peaks.
Add confectioners sugar and whisk gently till combined.
1 cup Confectioners sugar
Then add softened room temperature butter and vegetable shortening in batches and whisk for about 3-4 minutes or till it gets smooth and shiny.
¾ cup Vegetable shortening, 1 cup Unsalted butter softened
To this, add cooled strawberry puree and vanilla extract and whisk for 2 minutes.
Salt, a pinch, 2 teaspoon Vanilla extract, 2 drops Red food color (gel, optional)
Fill the piping bag fitted with your favorite frosting nozzle/tip and decorate the cupcakes as desired. Serve and enjoy!