Protein-butter cream glaze for cakes and cupcakes

Ingredients:

• 4 large egg whites
• 3/4 cup sugar
• A pinch of salt
• 240 g butter, room temperature

Preparation:

1. Combine egg whites, sugar, and salt in a heatproof bowl. Place over a double boiler and whisk until the sugar dissolves. Remove from the boiler and cool slightly.
2. Beat the egg mixture with a mixer on high speed until thick, about 12-15 minutes. Add the butter and continue beating until smooth.
   
   Use white cream icing to decorate the surface of the cake or as a layer.